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Yang K, Zhang Z, Tang M, Ren Y, Hu J, Zhen Q, Zheng J. Seabuckthorn (Hippophae rhamnoides L.) plantation degradation aggravates microbial metabolic C and P limitations on the Northern Loess Plateau in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:174088. [PMID: 38908587 DOI: 10.1016/j.scitotenv.2024.174088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 06/11/2024] [Accepted: 06/16/2024] [Indexed: 06/24/2024]
Abstract
Vegetation degradation in arid and semi-arid regions reduces plant C inputs to the soil, which can impede soil nutrient cycling because of the limited C source for microbial metabolism. However, whether vegetation degradation aggravates microbial nutrient limitation in degraded ecosystems in arid and semi-arid regions is not fully understood. Here, we investigated changes in soil enzyme activity and microbial nutrient limitation along a well-documented gradient of degraded seabuckthorn (Hippophae rhamnoides L.) (slightly degraded, canopy dieback <25 %, moderately degraded, canopy dieback 25 %-75 %, and severely degraded, canopy dieback >75 %) in Liang (long ridge) and gully channel locations in the Pisha Sandstone region of the Loess Plateau, China. We found that as the magnitude of seabuckthorn degradation increased, activities of C-acquiring enzymes and ratios of C:N and C:P enzymes (0.54-0.80 and 0.52-0.77, respectively) increased whereas the N:P enzyme ratio (0.93-0.99) decreased. Stoichiometric modelling further indicated that microorganisms were limited by soil C and P (vector angle >45°) in the seabuckthorn plantation region, and the degradation of seabuckthorn plantation aggravated microbial C and P limitations. Partial least squares path modelling revealed that seabuckthorn degradation (canopy dieback) was the main factor explaining microbial C limitation variations, while soil physicochemical properties (pH and soil moisture content) and understory plant parameters (litter biomass) were the major factors underlying microbial P limitation of long ridge and gully channel formations, respectively. Our findings highlight synergistic changes between aboveground and belowground processes, suggesting an unexpected negative effect of vegetation degradation on soil microbial community and nutrient cycling. These insights offer a direction for the development of plantation nutrients management strategies in semi-arid and arid areas.
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Affiliation(s)
- Kaiqi Yang
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China
| | - Zhiao Zhang
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China
| | - Mei Tang
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China
| | - Yunzhuo Ren
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China
| | - Jian Hu
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China
| | - Qing Zhen
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling 712100, China.
| | - Jiyong Zheng
- College of Natural Resources and Environment/State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A & F University, Yangling 712100, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling 712100, China
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2
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Lian X, Morfopoulos C, Gentine P. Water deficit and storm disturbances co-regulate Amazon rainforest seasonality. SCIENCE ADVANCES 2024; 10:eadk5861. [PMID: 39241070 PMCID: PMC11378916 DOI: 10.1126/sciadv.adk5861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 07/30/2024] [Indexed: 09/08/2024]
Abstract
Canopy leaf abundance of Amazon rainforests increases in the dry season but decreases in the wet season, contrary to earlier expectations of water stress adversely affecting plant functions. Drivers of this seasonality, particularly the role of water availability, remain debated. We introduce satellite-based ecophysiological indicators to demonstrate that Amazon rainforests are constrained by water during dry seasons despite light-driven canopy greening. Evidence includes a shifted partitioning of photosynthetically active radiation toward more isoprene emissions and synchronized declines in leaf and xylem water potentials. In addition, we find that convective storms attenuate light-driven ecosystem greening in the late dry season and then reverse to net leaf loss in the wet season, improving rainforest leaf area predictability by 24 to 31%. These findings highlight the susceptibility of Amazon rainforests to increasing risks of drought and windthrow disturbances under warming.
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Affiliation(s)
- Xu Lian
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
| | | | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- Center for Learning the Earth with Artificial intelligence and Physics (LEAP), Columbia University, New York, NY, USA
- Climate School, Columbia University, New York, NY, USA
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3
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Novick KA, Ficklin DL, Grossiord C, Konings AG, Martínez-Vilalta J, Sadok W, Trugman AT, Williams AP, Wright AJ, Abatzoglou JT, Dannenberg MP, Gentine P, Guan K, Johnston MR, Lowman LEL, Moore DJP, McDowell NG. The impacts of rising vapour pressure deficit in natural and managed ecosystems. PLANT, CELL & ENVIRONMENT 2024; 47:3561-3589. [PMID: 38348610 DOI: 10.1111/pce.14846] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 01/16/2024] [Accepted: 01/23/2024] [Indexed: 08/16/2024]
Abstract
An exponential rise in the atmospheric vapour pressure deficit (VPD) is among the most consequential impacts of climate change in terrestrial ecosystems. Rising VPD has negative and cascading effects on nearly all aspects of plant function including photosynthesis, water status, growth and survival. These responses are exacerbated by land-atmosphere interactions that couple VPD to soil water and govern the evolution of drought, affecting a range of ecosystem services including carbon uptake, biodiversity, the provisioning of water resources and crop yields. However, despite the global nature of this phenomenon, research on how to incorporate these impacts into resilient management regimes is largely in its infancy, due in part to the entanglement of VPD trends with those of other co-evolving climate drivers. Here, we review the mechanistic bases of VPD impacts at a range of spatial scales, paying particular attention to the independent and interactive influence of VPD in the context of other environmental changes. We then evaluate the consequences of these impacts within key management contexts, including water resources, croplands, wildfire risk mitigation and management of natural grasslands and forests. We conclude with recommendations describing how management regimes could be altered to mitigate the otherwise highly deleterious consequences of rising VPD.
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Affiliation(s)
- Kimberly A Novick
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana, USA
| | - Darren L Ficklin
- Department of Geography, Indiana University, Bloomington, Indiana, USA
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory (PERL), School of Architecture, Civil and Environmental Engineering (EPFL), Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, Lausanne, Switzerland
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, California, USA
| | - Jordi Martínez-Vilalta
- CREAF, Bellaterra, Catalonia, Spain
- Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Walid Sadok
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota, USA
| | - Anna T Trugman
- Department of Geography, University of California, Santa Barbara, California, USA
| | - A Park Williams
- Department of Geography, University of California, Los Angeles, California, USA
| | - Alexandra J Wright
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA
| | - John T Abatzoglou
- Management of Complex Systems Department, University of California, Merced, California, USA
| | - Matthew P Dannenberg
- Department of Geographical and Sustainability Sciences, University of Iowa, Iowa City, Iowa, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York, USA
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP), Columbia University, New York, New York, USA
| | - Kaiyu Guan
- Agroecosystem Sustainability Center, Institute for Sustainability, Energy, and Environment, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- Department of Natural Resources and Environmental Sciences, College of Agricultural, Consumers, and Environmental Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
- National Center for Supercomputing Applications, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Miriam R Johnston
- Department of Geographical and Sustainability Sciences, University of Iowa, Iowa City, Iowa, USA
| | - Lauren E L Lowman
- Department of Engineering, Wake Forest University, Winston-Salem, North Carolina, USA
| | - David J P Moore
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, USA
| | - Nate G McDowell
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
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4
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Jhaveri R, Cannanbilla L, Bhat KSA, Sankaran M, Krishnadas M. Anatomical traits explain drought response of seedlings from wet tropical forests. Ecol Evol 2024; 14:e70155. [PMID: 39224158 PMCID: PMC11366499 DOI: 10.1002/ece3.70155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 07/08/2024] [Accepted: 07/29/2024] [Indexed: 09/04/2024] Open
Abstract
Water availability regulates plant community dynamics but the drought response of seedlings remains poorly known, despite their vulnerability, especially for the Asian tropics. In particular, discerning how functional traits of seedlings mediate drought response can aid generalizable predictions of tree responses to global environmental change. We assessed interspecific variation in drought response explained by above- and below-ground seedling traits. We conducted a dry-down experiment in the greenhouse using 16 tree species from the humid forests of Western Ghats in southern India, chosen to represent differences in affinity to conditions of high and low seasonal drought (seasonality affiliation). We compared survival, growth, and photosynthetic performance under drought and well-watered conditions and assessed the extent to which species' responses were explained by seasonality affiliation and 12 traits of root, stem and leaf. We found that the species from seasonally dry forest reduced photosynthetic rate in drought compared with well-watered conditions, but seasonality affiliation did not explain differences in growth and survival. Performance in drought vs well-watered conditions were best explained by anatomical traits of xylem, veins and stomata. Species with larger xylem reduced their growth and photosynthesis to tolerate desiccation. In drought, species with smaller stomata correlated with lower survival even though photosynthetic activity decreased by a larger extent with larger stomata. Overall, anatomical traits of xylem and stomata, directly related to water transport and gas-exchange, played a more prominent role than commonly used traits (e.g., specific leaf area, leaf dry matter content) in explaining species response to drought, and may offer a good proxy for physiological traits related to drought tolerance of seedlings.
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Affiliation(s)
- Rishiddh Jhaveri
- CSIR – Centre for Cellular and Molecular BiologyHyderabadIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
| | - Lakshmipriya Cannanbilla
- CSIR – Centre for Cellular and Molecular BiologyHyderabadIndia
- Chair of Plant EcologyUniversity of BayreuthBayreuthGermany
| | - K. S. Arpitha Bhat
- Department of Life ScienceBangalore UniversityBangaloreIndia
- Ashoka Trust for Research in Ecology and the Environment (ATREE)BangaloreIndia
| | | | - Meghna Krishnadas
- CSIR – Centre for Cellular and Molecular BiologyHyderabadIndia
- National Centre for Biological Sciences, TIFRBangaloreIndia
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5
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Jacobsen AL, Venturas MD, Hacke UG, Pratt RB. Sap flow through partially embolized xylem vessel networks. PLANT, CELL & ENVIRONMENT 2024; 47:3375-3392. [PMID: 38826042 DOI: 10.1111/pce.14990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 05/16/2024] [Accepted: 05/18/2024] [Indexed: 06/04/2024]
Abstract
Sap is transported through numerous conduits in the xylem of woody plants along the path from the soil to the leaves. When all conduits are functional, vessel lumen diameter is a strong predictor of hydraulic conductivity. As vessels become embolized, sap movement becomes increasingly affected by factors operating at scales beyond individual conduits, creating resistances that result in hydraulic conductivity diverging from diameter-based estimates. These effects include pit resistances, connectivity, path length, network topology, and vessel or sector isolation. The impact of these factors varies with the level and distribution of emboli within the network, and manifest as alterations in the relationship between the number and diameter of embolized vessels with measured declines in hydraulic conductivity across vulnerability to embolism curves. Divergences between measured conductivity and diameter-based estimates reveal functional differences that arise because of species- and tissue-specific vessel network structures. Such divergences are not uniform, and xylem tissues may diverge in different ways and to differing degrees. Plants regularly operate under nonoptimal conditions and contain numerous embolized conduits. Understanding the hydraulic implications of emboli within a network and the function of partially embolized networks are critical gaps in our understanding of plants occurring within natural environments.
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Affiliation(s)
- Anna L Jacobsen
- Department of Biology, California State University, Bakersfield, California, USA
| | - Martin D Venturas
- Departamento de Sistemas y Recursos Naturales, Universidad Politécnica de Madrid, Madrid, Spain
| | - Uwe G Hacke
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Robert Brandon Pratt
- Department of Biology, California State University, Bakersfield, California, USA
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Penha D, Brum M, Alves LF, Domingues TF, Meneses A, Branches R, Restrepo-Coupe N, Oliveira RS, Moura JMS, Pequeno PACLA, Prohaska N, Saleska SR. Preserving isohydricity: vertical environmental variability explains Amazon forest water-use strategies. TREE PHYSIOLOGY 2024; 44:tpae088. [PMID: 39041710 DOI: 10.1093/treephys/tpae088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 07/07/2024] [Accepted: 07/18/2024] [Indexed: 07/24/2024]
Abstract
Increases in hydrological extremes, including drought, are expected for Amazon forests. A fundamental challenge for predicting forest responses lies in identifying ecological strategies which underlie such responses. Characterization of species-specific hydraulic strategies for regulating water-use, thought to be arrayed along an 'isohydric-anisohydric' spectrum, is a widely used approach. However, recent studies have questioned the usefulness of this classification scheme, because its metrics are strongly influenced by environments, and hence can lead to divergent classifications even within the same species. Here, we propose an alternative approach positing that individual hydraulic regulation strategies emerge from the interaction of environments with traits. Specifically, we hypothesize that the vertical forest profile represents a key gradient in drought-related environments (atmospheric vapor pressure deficit, soil water availability) that drives divergent tree water-use strategies for coordinated regulation of stomatal conductance (gs) and leaf water potentials (ΨL) with tree rooting depth, a proxy for water availability. Testing this hypothesis in a seasonal eastern Amazon forest in Brazil, we found that hydraulic strategies indeed depend on height-associated environments. Upper canopy trees, experiencing high vapor pressure deficit (VPD), but stable soil water access through deep rooting, exhibited isohydric strategies, defined by little seasonal change in the diurnal pattern of gs and steady seasonal minimum ΨL. In contrast, understory trees, exposed to less variable VPD but highly variable soil water availability, exhibited anisohydric strategies, with fluctuations in diurnal gs that increased in the dry season along with increasing variation in ΨL. Our finding that canopy height structures the coordination between drought-related environmental stressors and hydraulic traits provides a basis for preserving the applicability of the isohydric-to-anisohydric spectrum, which we show here may consistently emerge from environmental context. Our work highlights the importance of understanding how environmental heterogeneity structures forest responses to climate change, providing a mechanistic basis for improving models of tropical ecosystems.
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Affiliation(s)
- Deliane Penha
- Instituto de Biodiversidade e Florestas, Programa de Pós-Graduação Sociedade, Natureza e Desenvolvimento, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Mauro Brum
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
- Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas (UNICAMP), Barão Geraldo, Campinas SP 13083-970, Brazil
| | - Luciana F Alves
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, 619 Charles E. Young Drive East, La Kretz Hall, Suite 300, Box 951496, Los Angeles, CA 90095-1496, United States
| | - Tomas F Domingues
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Av. Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, SP 14040-901, Brazil
| | - Anderson Meneses
- Instituto de Biodiversidade e Florestas, Programa de Pós-Graduação Sociedade, Natureza e Desenvolvimento, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Laboratório de Inteligência Computacional, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Rardiles Branches
- Programa de Pós-Graduação em Meteorologia, Instituto Nacional de Pesquisas Espaciais, Rodovia Presidente Dutra, km 40, Cachoeira Paulista, São Paulo 12630-000, Brazil
| | - Natalia Restrepo-Coupe
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
| | - Rafael S Oliveira
- Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas (UNICAMP), Barão Geraldo, Campinas SP 13083-970, Brazil
| | - José Mauro S Moura
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Interdisciplinary and Intercultural Training Institute, Federal University of Western Para, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Pedro A C L Aurélio Pequeno
- Programa de Pós-graduação em Recursos Naturais (PRONAT), Universidade Federal de Roraima, Av. Cap. Ene Garcez, 2413, Aeroporto, Roraima, Boa Vista, 69310-000, Brazil
| | - Neill Prohaska
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
| | - Scott R Saleska
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
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Ziegler C, Cochard H, Stahl C, Foltzer L, Gérard B, Goret JY, Heuret P, Levionnois S, Maillard P, Bonal D, Coste S. Residual water losses mediate the trade-off between growth and drought survival across saplings of 12 tropical rainforest tree species with contrasting hydraulic strategies. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4128-4147. [PMID: 38613495 DOI: 10.1093/jxb/erae159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 04/12/2024] [Indexed: 04/15/2024]
Abstract
Knowledge of the physiological mechanisms underlying species vulnerability to drought is critical for better understanding patterns of tree mortality. Investigating plant adaptive strategies to drought should thus help to fill this knowledge gap, especially in tropical rainforests exhibiting high functional diversity. In a semi-controlled drought experiment using 12 rainforest tree species, we investigated the diversity in hydraulic strategies and whether they determined the ability of saplings to use stored non-structural carbohydrates during an extreme imposed drought. We further explored the importance of water- and carbon-use strategies in relation to drought survival through a modelling approach. Hydraulic strategies varied considerably across species with a continuum between dehydration tolerance and avoidance. During dehydration leading to hydraulic failure and irrespective of hydraulic strategies, species showed strong declines in whole-plant starch concentrations and maintenance, or even increases in soluble sugar concentrations, potentially favouring osmotic adjustments. Residual water losses mediated the trade-off between time to hydraulic failure and growth, indicating that dehydration avoidance is an effective drought-survival strategy linked to the 'fast-slow' continuum of plant performance at the sapling stage. Further investigations on residual water losses may be key to understanding the response of tropical rainforest tree communities to climate change.
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Affiliation(s)
- Camille Ziegler
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Hervé Cochard
- Université Clermont-Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - Clément Stahl
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Louis Foltzer
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Bastien Gérard
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Jean-Yves Goret
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Patrick Heuret
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ. Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Sébastien Levionnois
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ. Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Pascale Maillard
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Damien Bonal
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Sabrina Coste
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
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Chen L, He K, Shi P, Lian M, Yao W, Niklas KJ. Influence of tree size on the scaling relationships of lamina and petiole traits: A case study using Camptotheca acuminata Decne. Ecol Evol 2024; 14:e70066. [PMID: 39035043 PMCID: PMC11258476 DOI: 10.1002/ece3.70066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/28/2024] [Accepted: 07/10/2024] [Indexed: 07/23/2024] Open
Abstract
There is a lack of research on whether tree size affects lamina and petiole biomass allocation patterns, whereas the trade-off between leaf biomass allocated to the lamina and the petiole is of significance when considering the hydraulic and mechanical function of the leaf as a whole. Here, Camptotheca acuminata Decne was selected for study because of the availability of trees differing in size growing under the same conditions. A total of 600 leaves for two tree size groups and 300 leaves per group differing in height and trunk diameter were collected. The lamina fresh mass (LFM), lamina dry mass (LDM), lamina area (LA), petiole fresh mass (PFM), and petiole length (PL) of each leaf was measured, and reduced major axis regression protocols were used to determine the scaling relationships among the five functional traits. The bootstrap percentile method was used to determine if the scaling exponents of the traits differed significantly between the two tree size groups. The results indicated that (i) there was a significant difference in the LFM, LDM, PFM, PL, LMA, LFMA and PFM/LFM between large and small trees, but no significant difference in LA; (ii) the LA versus LFM, LA versus LDM, LFM versus PFM, LA versus PFM, and PL versus PFM scaling relationships of the two groups were allometric (i.e., not isometric); (iii) there were significant differences in the scaling exponents of LA versus LFM, LA versus PFM, PL versus PFM between the two groups, but there was no significant difference in the LFM versus PFM scaling relationship between the two groups of trees. The data were also consistent with the phenomenon known as "diminishing returns". These data indicate that tree size influences leaf biomass allocation patterns in ways that can potentially influence overall plant growth, and therefore have an important bearing on life-history strategies.
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Affiliation(s)
- Long Chen
- Co‐Innovation Centre for Sustainable Forestry in Southern China, Bamboo Research Institute, College of Ecology and EnvironmentNanjing Forestry UniversityNanjingChina
| | - Ke He
- School of ArchitectureHuaqiao UniversityXiamenChina
- School of Civil Engineering and ArchitectureXiamen University of TechnologyXiamenChina
| | - Peijian Shi
- Co‐Innovation Centre for Sustainable Forestry in Southern China, Bamboo Research Institute, College of Ecology and EnvironmentNanjing Forestry UniversityNanjingChina
| | - Meng Lian
- Co‐Innovation Centre for Sustainable Forestry in Southern China, Bamboo Research Institute, College of Ecology and EnvironmentNanjing Forestry UniversityNanjingChina
| | - Weihao Yao
- Co‐Innovation Centre for Sustainable Forestry in Southern China, Bamboo Research Institute, College of Ecology and EnvironmentNanjing Forestry UniversityNanjingChina
| | - Karl J. Niklas
- School of Integrative Plant ScienceCornell UniversityIthacaNew YorkUSA
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Anfodillo T, Olson ME. Stretched sapwood, ultra-widening permeability and ditching da Vinci: revising models of plant form and function. ANNALS OF BOTANY 2024; 134:19-42. [PMID: 38634673 PMCID: PMC11161570 DOI: 10.1093/aob/mcae054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 04/14/2024] [Indexed: 04/19/2024]
Abstract
BACKGROUND The mechanisms leading to dieback and death of trees under drought remain unclear. To gain an understanding of these mechanisms, addressing major empirical gaps regarding tree structure-function relations remains essential. SCOPE We give reasons to think that a central factor shaping plant form and function is selection simultaneously favouring constant leaf-specific conductance with height growth and isometric (1:1) scaling between leaf area and the volume of metabolically active sink tissues ('sapwood'). Sapwood volume-leaf area isometry implies that per-leaf area sapwood volumes become transversely narrower with height growth; we call this 'stretching'. Stretching means that selection must favour increases in permeability above and beyond that afforded by tip-to-base conduit widening ("ultra-widening permeability"), via fewer and wider vessels or tracheids with larger pits or larger margo openings. Leaf area-metabolically active sink tissue isometry would mean that it is unlikely that larger trees die during drought because of carbon starvation due to greater sink-source relationships as compared to shorter plants. Instead, an increase in permeability is most plausibly associated with greater risk of embolism, and this seems a more probable explanation of the preferential vulnerability of larger trees to climate change-induced drought. Other implications of selection favouring constant per-leaf area sapwood construction and maintenance costs are departure from the da Vinci rule expectation of similar sapwood areas across branching orders, and that extensive conduit furcation in the stem seems unlikely. CONCLUSIONS Because all these considerations impact the likelihood of vulnerability to hydraulic failure versus carbon starvation, both implicated as key suspects in forest mortality, we suggest that these predictions represent essential priorities for empirical testing.
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Affiliation(s)
- Tommaso Anfodillo
- Department Territorio e Sistemi Agro-Forestali, University of Padova, Legnaro (PD) 35020, Italy
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
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10
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Van Passel J, Bernardino PN, Lhermitte S, Rius BF, Hirota M, Conradi T, de Keersmaecker W, Van Meerbeek K, Somers B. Critical slowing down of the Amazon forest after increased drought occurrence. Proc Natl Acad Sci U S A 2024; 121:e2316924121. [PMID: 38768350 PMCID: PMC11145287 DOI: 10.1073/pnas.2316924121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 04/05/2024] [Indexed: 05/22/2024] Open
Abstract
Dynamic ecosystems, such as the Amazon forest, are expected to show critical slowing down behavior, or slower recovery from recurrent small perturbations, as they approach an ecological threshold to a different ecosystem state. Drought occurrences are becoming more prevalent across the Amazon, with known negative effects on forest health and functioning, but their actual role in the critical slowing down patterns still remains elusive. In this study, we evaluate the effect of trends in extreme drought occurrences on temporal autocorrelation (TAC) patterns of satellite-derived indices of vegetation activity, an indicator of slowing down, between 2001 and 2019. Differentiating between extreme drought frequency, intensity, and duration, we investigate their respective effects on the slowing down response. Our results indicate that the intensity of extreme droughts is a more important driver of slowing down than their duration, although their impacts vary across the different Amazon regions. In addition, areas with more variable precipitation are already less ecologically stable and need fewer droughts to induce slowing down. We present findings indicating that most of the Amazon region does not show an increasing trend in TAC. However, the predicted increase in extreme drought intensity and frequency could potentially transition significant portions of this ecosystem into a state with altered functionality.
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Affiliation(s)
- Johanna Van Passel
- Division Forest, Nature and Landscape, KU Leuven, Leuven3001, Belgium
- KU Leuven Plant Institute, KU Leuven, Leuven3001, Belgium
| | - Paulo N. Bernardino
- Division Forest, Nature and Landscape, KU Leuven, Leuven3001, Belgium
- Department of Plant Biology, University of Campinas, Campinas-SP13083-970, Brazil
| | - Stef Lhermitte
- Division Forest, Nature and Landscape, KU Leuven, Leuven3001, Belgium
- Department Geoscience & Remote Sensing, Delft University of Technology, Delft2600, The Netherlands
| | - Bianca F. Rius
- Center for Meteorological and Climatic Research Applied to Agriculture, University of Campinas, Campinas-SP13083-970, Brazil
- Interdisciplinary Environmental Studies Laboratory, Department of Physics, Federal University of Santa Catarina, Florianópolis, SC88040-900, Brazil
| | - Marina Hirota
- Department of Plant Biology, University of Campinas, Campinas-SP13083-970, Brazil
- Interdisciplinary Environmental Studies Laboratory, Department of Physics, Federal University of Santa Catarina, Florianópolis, SC88040-900, Brazil
| | - Timo Conradi
- Plant Ecology, University of Bayreuth, Bayreuth95447, Germany
| | | | - Koenraad Van Meerbeek
- Division Forest, Nature and Landscape, KU Leuven, Leuven3001, Belgium
- KU Leuven Plant Institute, KU Leuven, Leuven3001, Belgium
| | - Ben Somers
- Division Forest, Nature and Landscape, KU Leuven, Leuven3001, Belgium
- KU Leuven Plant Institute, KU Leuven, Leuven3001, Belgium
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11
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Ramirez JA, Craven D, Herrera D, Posada JM, Reu B, Sierra CA, Hoch G, Handa IT, Messier C. Non-structural carbohydrate concentrations in tree organs vary across biomes and leaf habits, but are independent of the fast-slow plant economic spectrum. FRONTIERS IN PLANT SCIENCE 2024; 15:1375958. [PMID: 38766471 PMCID: PMC11099217 DOI: 10.3389/fpls.2024.1375958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 04/19/2024] [Indexed: 05/22/2024]
Abstract
Carbohydrate reserves play a vital role in plant survival during periods of negative carbon balance. Under a carbon-limited scenario, we expect a trade-offs between carbon allocation to growth, reserves, and defense. A resulting hypothesis is that carbon allocation to reserves exhibits a coordinated variation with functional traits associated with the 'fast-slow' plant economics spectrum. We tested the relationship between non-structural carbohydrates (NSC) of tree organs and functional traits using 61 angiosperm tree species from temperate and tropical forests with phylogenetic hierarchical Bayesian models. Our results provide evidence that NSC concentrations in stems and branches are decoupled from plant functional traits. while those in roots are weakly coupled with plant functional traits. In contrast, we found that variation between NSC concentrations in leaves and the fast-slow trait spectrum was coordinated, as species with higher leaf NSC had trait values associated with resource conservative species, such as lower SLA, leaf N, and leaf P. We also detected a small effect of leaf habit on the variation of NSC concentrations in branches and roots. Efforts to predict the response of ecosystems to global change will need to integrate a suite of plant traits, such as NSC concentrations in woody organs, that are independent of the 'fast-slow' plant economics spectrum and that capture how species respond to a broad range of global change drivers.
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Affiliation(s)
- Jorge Andres Ramirez
- Facultad de Ciencias Agrarias, Universidad del Cauca, Popayán, Colombia
- Centre d’Étude de la Forêt (CEF), Université du Québec à Montréal, Montréal, QC, Canada
| | - Dylan Craven
- GEMA Center for Genomics, Ecology and Environment, Universidad Mayor, Huechuraba, Santiago, Chile
- Data Observatory Foundation, and Technology Center, Santiago, Chile
| | - David Herrera
- Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Juan Manuel Posada
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Bjorn Reu
- School of Biology, Universidad Industrial de Santander, Bucaramanga, Colombia
| | | | - Guenter Hoch
- Department of Environmental Sciences – Botany, University of Basel, Basel, Switzerland
| | - Ira Tanya Handa
- Centre d’Étude de la Forêt (CEF), Université du Québec à Montréal, Montréal, QC, Canada
| | - Christian Messier
- Centre d’Étude de la Forêt (CEF), Université du Québec à Montréal, Montréal, QC, Canada
- Institut des Sciences de la Foret Tempérée, Université du Québec en Outaouais, Ripon, QC, Canada
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12
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Sterck FJ, Song Y, Poorter L. Drought- and heat-induced mortality of conifer trees is explained by leaf and growth legacies. SCIENCE ADVANCES 2024; 10:eadl4800. [PMID: 38608026 PMCID: PMC11014445 DOI: 10.1126/sciadv.adl4800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 03/08/2024] [Indexed: 04/14/2024]
Abstract
An increased frequency and severity of droughts and heat waves have resulted in increased tree mortality and forest dieback across the world, but underlying mechanisms are poorly understood. We used a common garden experiment with 20 conifer tree species to quantify mortality after three consecutive hot, dry summers and tested whether mortality could be explained by putative underlying mechanisms, such as stem hydraulics and legacies affected by leaf life span and stem growth responses to previous droughts. Mortality varied from 0 to 79% across species and was not affected by hydraulic traits. Mortality increased with species' leaf life span probably because leaf damage caused crown dieback and contributed to carbon depletion and bark beetle damage. Mortality also increased with lower growth resilience, which may exacerbate the contribution of carbon depletion and bark beetle sensitivity to tree mortality. Our study highlights how ecological legacies at different time scales can explain tree mortality in response to hot, dry periods and climate change.
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Affiliation(s)
- Frank J. Sterck
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
| | - Yanjun Song
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
- School of Biological Sciences, Washington State University, P.O. Box 644236, Pullman, WA 99164-4236, USA
| | - Lourens Poorter
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
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13
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Cox AJF, González-Caro S, Meir P, Hartley IP, Restrepo Z, Villegas JC, Sanchez A, Mercado LM. Variable thermal plasticity of leaf functional traits in Andean tropical montane forests. PLANT, CELL & ENVIRONMENT 2024; 47:731-750. [PMID: 38047584 DOI: 10.1111/pce.14778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 11/08/2023] [Accepted: 11/21/2023] [Indexed: 12/05/2023]
Abstract
Tropical montane forests (TMFs) are biodiversity hotspots and provide vital ecosystem services, but they are disproportionately vulnerable to climate warming. In the Andes, cold-affiliated species from high elevations are being displaced at the hot end of their thermal distributions by warm-affiliated species migrating upwards from lower elevations, leading to compositional shifts. Leaf functional traits are strong indicators of plant performance and at the community level have been shown to vary along elevation gradients, reflecting plant adaptations to different environmental niches. However, the plastic response of such traits to relatively rapid temperature change in Andean TMF species remains unknown. We used three common garden plantations within a thermosequence in the Colombian Andes to investigate the warming and cooling responses of key leaf functional traits in eight cold- and warm-affiliated species with variable thermal niches. Cold-affiliated species shifted their foliar nutrient concentrations when exposed to warming, while all other traits did not significantly change; contrastingly, warm-affiliated species were able to adjust structural, nutrient and water-use efficiency traits from acquisitive to conservative strategies in response to cooling. Our findings suggest that cold-affiliated species will struggle to acclimate functional traits to warming, conferring warm-affiliated species a competitive advantage under climate change.
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Affiliation(s)
- Andrew J F Cox
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Sebastián González-Caro
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Division of Plant Sciences, Research, The Australian National University, Canberra, Australia
| | - Iain P Hartley
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Zorayda Restrepo
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
- Grupo de Servicios Ecositémicos y Cambio Climático, Corporación, Medellín, Colombia
| | - Juan C Villegas
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
| | - Adriana Sanchez
- Programa de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Lina M Mercado
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
- UK Centre for Ecology & Hydrology, Crowmarsh-Gifford, Wallingford, UK
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14
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Kang J, Shen H, Zhang S, Xu L, Tang Z, Tang Y, Fang J. Contrasting growth responses to drought in three tree species widely distributed in northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168331. [PMID: 37931814 DOI: 10.1016/j.scitotenv.2023.168331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/12/2023] [Accepted: 11/02/2023] [Indexed: 11/08/2023]
Abstract
Tree species-specific responses to drought are urgently needed for assessing the impacts of current climate change on forest ecosystems. Here, we characterized the resistance, recovery, resilience, and growth recovery periods in response to different drought events based on tree-ring width index data (>30 years) for three tree species widely distributed in northern China, among which larch (Larix principis-rupprechtii Mayr) and Mongolian pine (Pinus sylvestris L. var. mongolica Litv.) are two major species used for afforestation, and birch (Betula platyphylla Suk.) is one of the most common natural tree species. Despite no significant effects of mild drought on tree growth, severe drought events significantly reduced the growth of all species, with contrasting species-specific responses. Larch trees had the lowest resistance and resilience among the three species, and Mongolian pine trees were more resistant but had a longer recovery period than birch trees. The drought responses varied with tree size. Large Mongolian pine and birch trees were more resistant but large larch trees were much more vulnerable than small trees during severe droughts. Smaller birch trees had higher resilience to severe droughts. Our study shows species-specific differences in drought responses and suggests that drought responses are tree-size dependent and drought-intensity associated, which further provides a guidance for selecting optimal cultivated tree species and designing forest managements in this region.
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Affiliation(s)
- Jie Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Haihua Shen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Siyi Zhang
- Institute of Ecology, College of Urban and Environmental Sciences, Key Laboratory of Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Longchao Xu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Zhiyao Tang
- Institute of Ecology, College of Urban and Environmental Sciences, Key Laboratory of Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Yanhong Tang
- Institute of Ecology, College of Urban and Environmental Sciences, Key Laboratory of Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Jingyun Fang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China; Institute of Ecology, College of Urban and Environmental Sciences, Key Laboratory of Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
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15
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Paschalis A, De Kauwe MG, Sabot M, Fatichi S. When do plant hydraulics matter in terrestrial biosphere modelling? GLOBAL CHANGE BIOLOGY 2024; 30:e17022. [PMID: 37962234 PMCID: PMC10952296 DOI: 10.1111/gcb.17022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023]
Abstract
The ascent of water from the soil to the leaves of vascular plants, described by the study of plant hydraulics, regulates ecosystem responses to environmental forcing and recovery from stress periods. Several approaches to model plant hydraulics have been proposed. In this study, we introduce four different versions of plant hydraulics representations in the terrestrial biosphere model T&C to understand the significance of plant hydraulics to ecosystem functioning. We tested representations of plant hydraulics, investigating plant water capacitance, and long-term xylem damages following drought. The four models we tested were a combination of representations including or neglecting capacitance and including or neglecting xylem damage legacies. Using the models at six case studies spanning semiarid to tropical ecosystems, we quantify how plant xylem flow, plant water storage and long-term xylem damage can modulate overall water and carbon dynamics across multiple time scales. We show that as drought develops, models with plant hydraulics predict a slower onset of plant water stress, and a diurnal variability of water and carbon fluxes closer to observations. Plant water storage was found to be particularly important for the diurnal dynamics of water and carbon fluxes, with models that include plant water capacitance yielding better results. Models including permanent damage to conducting plant tissues show an additional significant drought legacy effect, limiting plant productivity during the recovery phase following major droughts. However, when considering ecosystem responses to the observed climate variability, plant hydraulic modules alone cannot significantly improve the overall model performance, even though they reproduce more realistic water and carbon dynamics. This opens new avenues for model development, explicitly linking plant hydraulics with additional ecosystem processes, such as plant phenology and improved carbon allocation algorithms.
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Affiliation(s)
- Athanasios Paschalis
- Department of Civil and Environmental EngineeringImperial College LondonLondonUK
| | | | - Manon Sabot
- ARC Centre of Excellence for Climate Extremes and Climate Change Research CentreUniversity of New South WalesSydneyNew South WalesAustralia
| | - Simone Fatichi
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
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16
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Wang X, Xu T, Xu C, Liu H, Chen Z, Li Z, Li X, Wu X. Enhanced growth resistance but no decline in growth resilience under long-term extreme droughts. GLOBAL CHANGE BIOLOGY 2024; 30:e17038. [PMID: 37987223 DOI: 10.1111/gcb.17038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 10/19/2023] [Accepted: 10/29/2023] [Indexed: 11/22/2023]
Abstract
The frequency, intensity, and duration of extreme droughts, with devastating impacts on tree growth and survival, have increased with climate change over the past decades. Assessing growth resistance and resilience to drought is a crucial prerequisite for understanding the responses of forest functioning to drought events. However, the responses of growth resistance and resilience to extreme droughts with different durations across different climatic zones remain unclear. Here, we investigated the spatiotemporal patterns in growth resistance and resilience in response to extreme droughts with different durations during 1901-2015, relying on tree-ring chronologies from 2389 forest stands over the mid- and high-latitudinal Northern Hemisphere, species-specific plant functional traits, and diverse climatic factors. The findings revealed that growth resistance and resilience under 1-year droughts were higher in humid regions than in arid regions. Significant higher growth resistance was observed under 2-year droughts than under 1-year droughts in both arid and humid regions, while growth resilience did not show a significant difference. Temporally, tree growth became less resistant and resilient to 1-year droughts in 1980-2015 than in 1901-1979 in both arid and humid regions. As drought duration lengthened, the predominant impacts of climatic factors on growth resistance and resilience weakened and instead foliar economic traits, plant hydraulic traits, and soil properties became much more important in both climatic regions; in addition, such trends were also observed temporally. Finally, we found that most of the Earth system models (ESMs) used in this study overestimated growth resistance and underestimated growth resilience under both 1-year and 2-year droughts. A comprehensive ecophysiological understanding of tree growth responses to longer and intensified drought events is urgently needed, and a specific emphasis should be placed on improving the performance of ESMs.
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Affiliation(s)
- Xiaona Wang
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Beijing Normal University, Beijing, China
- Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Taoran Xu
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Beijing Normal University, Beijing, China
- Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Chenxi Xu
- Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | - Hongyan Liu
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Zhenju Chen
- Tree-Ring Laboratory, Research Station of Liaohe-River Plain Forest Ecosystem CFERN, College of Forestry, Shenyang Agricultural University, Shenyang, China
| | - Zongshan Li
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Ximeng Li
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Xiuchen Wu
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Beijing Normal University, Beijing, China
- Faculty of Geographical Science, Beijing Normal University, Beijing, China
- Academy of Plateau Science and Sustainability, People's Government of Qinghai Province & Beijing Normal University, Xining, China
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17
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Li F, Qing T, Wu F, Yue K, Zhu J, Ni X. Trade-off in the partitioning of recent photosynthate carbon under global change. GLOBAL CHANGE BIOLOGY 2024; 30:e17110. [PMID: 38273584 DOI: 10.1111/gcb.17110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 01/27/2024]
Abstract
There may be trade-offs in the allocation patterns of recent photosynthetic carbon (RPC) allocation in response to environmental changes, with a greater proportion of RPC being directed towards compartments experiencing limited resource availability. Alternatively, the allocation of RPC could shift from sources to sinks as plants processing excess photosynthates. It prompts the question: Does the pattern of RPC allocation vary under global changes? If so, is this variation driven by optimal or by residual C allocation strategies? We conducted a meta-analysis by complicating 273 pairwise observations from 55 articles with 13 C or 14 C pulse or continuous labeling to assess the partitioning of RPC in biomass (leaf, stem, shoot, and root), soil pools (soil organic C, rhizosphere, and microbial biomass C) and CO2 fluxes under elevated CO2 (eCO2 ), warming, drought and nitrogen (N) addition. We propose that the increased allocation of RPC to belowground under sufficient CO2 results from the excretion of excess photosynthates. Warming led to a significant reduction in the percentage of RPC allocated to shoots, alongside an increase in roots allocation, although this was not statistically significant. This pattern is due to the reduced water availability resulting from warming. In conditions of drought, there was a notable increase in the partitioning of RPC to stems (+7.25%) and roots (+36.38%), indicative of a greater investment of RPC in roots for accessing water from deeper soil. Additionally, N addition led to a heightened allocation of RPC in leaves (+10.18%) and shoots (+5.78%), while reducing its partitioning in soil organic C (-8.92%). Contrary to the residual C partitioning observed under eCO2 , the alterations in RPC partitioning in response to warming, drought, and N supplementation are more comprehensively explained through the lens of optimal partitioning theory, showing a trade-off in the partitioning of RPC under global change.
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Affiliation(s)
- Fangping Li
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Ting Qing
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Fuzhong Wu
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China
| | - Kai Yue
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China
| | - Jingjing Zhu
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Xiangyin Ni
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China
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18
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Wang H, Ciais P, Sitch S, Green JK, Tao S, Fu Z, Albergel C, Bastos A, Wang M, Fawcett D, Frappart F, Li X, Liu X, Li S, Wigneron JP. Anthropogenic disturbance exacerbates resilience loss in the Amazon rainforests. GLOBAL CHANGE BIOLOGY 2024; 30:e17006. [PMID: 37909670 DOI: 10.1111/gcb.17006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 09/03/2023] [Accepted: 10/10/2023] [Indexed: 11/03/2023]
Abstract
Uncovering the mechanisms that lead to Amazon forest resilience variations is crucial to predict the impact of future climatic and anthropogenic disturbances. Here, we apply a previously used empirical resilience metrics, lag-1 month temporal autocorrelation (TAC), to vegetation optical depth data in C-band (a good proxy of the whole canopy water content) in order to explore how forest resilience variations are impacted by human disturbances and environmental drivers in the Brazilian Amazon. We found that human disturbances significantly increase the risk of critical transitions, and that the median TAC value is ~2.4 times higher in human-disturbed forests than that in intact forests, suggesting a much lower resilience in disturbed forests. Additionally, human-disturbed forests are less resilient to land surface heat stress and atmospheric water stress than intact forests. Among human-disturbed forests, forests with a more closed and thicker canopy structure, which is linked to a higher forest cover and a lower disturbance fraction, are comparably more resilient. These results further emphasize the urgent need to limit deforestation and degradation through policy intervention to maintain the resilience of the Amazon rainforests.
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Affiliation(s)
- Huan Wang
- College of Urban and Environmental Sciences, Peking University, Beijing, China
- INRAE, UMR1391 ISPA, Université de Bordeaux, Villenave d'Ornon, France
- Laboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS/UVSQ/Université Paris Saclay, Gif-sur-Yvette, France
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS/UVSQ/Université Paris Saclay, Gif-sur-Yvette, France
| | - Stephen Sitch
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Julia K Green
- Department of Environmental Science, The University of Arizona, Tucson, Arizona, USA
| | - Shengli Tao
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Zheng Fu
- Laboratoire des Sciences du Climat et de l'Environnement, CEA/CNRS/UVSQ/Université Paris Saclay, Gif-sur-Yvette, France
| | | | - Ana Bastos
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Mengjia Wang
- School of Geoscience and Technology, Zhengzhou University, Zhengzhou, China
| | - Dominic Fawcett
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Swiss Federal Institute for Forest Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Frédéric Frappart
- INRAE, UMR1391 ISPA, Université de Bordeaux, Villenave d'Ornon, France
| | - Xiaojun Li
- INRAE, UMR1391 ISPA, Université de Bordeaux, Villenave d'Ornon, France
| | - Xiangzhuo Liu
- INRAE, UMR1391 ISPA, Université de Bordeaux, Villenave d'Ornon, France
| | - Shuangcheng Li
- College of Urban and Environmental Sciences, Peking University, Beijing, China
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19
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Waite PA, Leuschner C, Delzon S, Triadiati T, Saad A, Schuldt B. Plasticity of wood and leaf traits related to hydraulic efficiency and safety is linked to evaporative demand and not soil moisture in rubber (Hevea brasiliensis). TREE PHYSIOLOGY 2023; 43:2131-2149. [PMID: 37707940 DOI: 10.1093/treephys/tpad113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/23/2023] [Accepted: 08/28/2023] [Indexed: 09/15/2023]
Abstract
The predicted increase of drought intensity in South-East Asia has raised concern about the sustainability of rubber (Hevea brasiliensis Müll. Arg.) cultivation. In order to quantify the degree of phenotypic plasticity in this important tree crop species, we analysed a set of wood and leaf traits related to the hydraulic safety and efficiency in PB260 clones from eight small-holder plantations in Jambi province, Indonesia, representing a gradient in local microclimatic and edaphic conditions. Across plots, branch embolism resistance (P50) ranged from -2.14 to -2.58 MPa. The P50 and P88 values declined, and the hydraulic safety margin increased, with an increase in the mean annual vapour pressure deficit (VPD). Among leaf traits, only the changes in specific leaf area were related to the differences in evaporative demand. These variations of hydraulic trait values were not related to soil moisture levels. We did not find a trade-off between hydraulic safety and efficiency, but vessel density (VD) emerged as a major trait associated with both safety and efficiency. The VD, and not vessel diameter, was closely related to P50 and P88 as well as to specific hydraulic conductivity, the lumen-to-sapwood area ratio and the vessel grouping index. In conclusion, our results demonstrate some degree of phenotypic plasticity in wood traits related to hydraulic safety in this tropical tree species, but this is only in response to the local changes in evaporative demand and not soil moisture. Given that VPD may increasingly limit plant growth in a warmer world, our results provide evidence of hydraulic trait changes in response to a rising evaporative demand.
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Affiliation(s)
- Pierre-André Waite
- Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Straße 7, Tharandt 01737, Germany
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen 37073, Germany
| | - Christoph Leuschner
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen 37073, Germany
| | - Sylvain Delzon
- Department of Biodiversity, Genes, and Communities (BIOGECO), Institut National de Recherche pour Agriculture, Alimentation et Environnement (INRAE), Université Bordeaux, Bat. 2 Allée Geoffroy St-Hilaire, Pessac 33615, France
| | - Triadiati Triadiati
- Department of Biology, Faculty of Mathematics and Natural Sciences, Bogor IPB University, Darmaga Campus, Bogor 16680, Indonesia
| | - Asmadi Saad
- Department of Soil Science, University of Jambi, Jalan Raya Jambi Muara Bulian KM 15 Mandalo Indah, Jambi, Sumatra 36361, Indonesia
| | - Bernhard Schuldt
- Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Straße 7, Tharandt 01737, Germany
- Plant Ecology, Albrecht von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen 37073, Germany
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20
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Zhang Q, Zhao H, Cheng W, Cong N, Wang X, Liang H, Li X. Increased productivity of temperate vegetation in the preceding year drives early spring phenology in the subsequent year in northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166676. [PMID: 37673244 DOI: 10.1016/j.scitotenv.2023.166676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/23/2023] [Accepted: 08/27/2023] [Indexed: 09/08/2023]
Abstract
Under global warming, rising temperature have advanced spring phenology in recent decades. However, the internal physiological mechanisms driving changes in spring phenology still remain poorly understood. Here, we investigated the effects of temperate vegetation gross primary productivity (GPP) during the preceding year on spring phenology of the subsequent year based on the start of growing season (SOS) extracted from NDVI datasets between 1982 and 2015. We found that the preceding year's GPP had an effect on the subsequent year's SOS, equivalent to 33 %-50 % of effect of the preseason's mean temperature. Specifically, in the temperate and semi-humid or humid conditions, the preceding year's GPP had a stronger effect on SOS than in boreal or semi-arid conditions. In addition, the SOS of the dwarf vegetation, with less transport pressure and higher carbon concentrations, was more sensitive to the preceding year's GPP than that of tall forests. We found the effects of the preceding year's GPP on SOS varied with space and vegetation types. Therefore, the physiological mechanism should be considered in future spring phenology model separately according to space and vegetation types, to improve the accuracy of future phenology and then global carbon sequestration predictions.
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Affiliation(s)
- Qi Zhang
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China
| | - Hongfang Zhao
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China; Key Laboratory of Geographic Information Science, Ministry of Education, East China Normal University, Shanghai 200241, China; Key Laboratory of Spatial-temporal Big Data Analysis and Application of Natural Resources in Megacities, Ministry of Natural Resources, Shanghai 200241, China.
| | - Wanying Cheng
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China
| | - Nan Cong
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuhui Wang
- Institute of Carbon Neutrality, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100091, China
| | - Hangqi Liang
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China
| | - Xia Li
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China; Key Laboratory of Geographic Information Science, Ministry of Education, East China Normal University, Shanghai 200241, China; Key Laboratory of Spatial-temporal Big Data Analysis and Application of Natural Resources in Megacities, Ministry of Natural Resources, Shanghai 200241, China
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21
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Qiu R, Han G, Li S, Tian F, Ma X, Gong W. Soil moisture dominates the variation of gross primary productivity during hot drought in drylands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 899:165686. [PMID: 37482354 DOI: 10.1016/j.scitotenv.2023.165686] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/25/2023]
Abstract
The frequency and severity of hot drought will increase in the future due to impact of climate change and human activities, threatening the sustainability of terrestrial ecosystems and human societies. Hot drought is a typical type of drought event, high vapor pressure deficit (VPD) and low soil moisture (SM) are its main characteristics of hot drought, with increasing water stress on vegetation and exacerbating hydrological drought and ecosystem risks. However, our understanding of the effects of high VPD and low SM on vegetation productivity is limited, because these two variables are strongly coupled and influenced by other climatic drivers. The southwestern United States experienced one of the most severe hot drought events on record in 2020. In this study, we used SM and gross primary productivity (GPP) datasets from Soil Moisture Active and Passive (SMAP), as well as VPD and other meteorological datasets from gridMET. We decoupled the effects of different meteorological factors on GPP at monthly and daily scales using partial correlation analysis, partial least squares regression, and binning methods. We found that SM anomalies contribute more to GPP anomalies than VPD anomalies at monthly and daily scales. Especially at the daily scale, as the decoupled SM anomalies increased, the GPP anomalies increased. However, there is no significant change in GPP anomalies as VPD increases. For all the vegetation types and arid zones, SM dominated the variation in GPP, followed by VPD or maximum temperature. At the flux tower scale, decoupled soil water content (SWC) also dominated changes in GPP, compared to VPD. In the next century, hot drought will occur frequently in dryland regions, where GPP is one of the highest uncertainties in terrestrial ecosystems. Our study has important implications for identifying the strong coupling of meteorological factors and their impact on vegetation under climate change.
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Affiliation(s)
- Ruonan Qiu
- School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China
| | - Ge Han
- School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China; Perception and Effectiveness Assessment for Carbon-neutral Efforts, Engineering Research Center of Ministry of Education, Wuhan, China.
| | - Siwei Li
- School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China.
| | - Feng Tian
- School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China
| | - Xin Ma
- State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, China
| | - Wei Gong
- Electronic Information School, Wuhan University, Wuhan 430079, China; Hubei Luojia Laboratory, Wuhan, China
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22
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Zhang G, Mao Z, Maillard P, Brancheriau L, Gérard B, Engel J, Fortunel C, Heuret P, Maeght JL, Martínez-Vilalta J, Stokes A. Functional trade-offs are driven by coordinated changes among cell types in the wood of angiosperm trees from different climates. THE NEW PHYTOLOGIST 2023; 240:1162-1176. [PMID: 37485789 DOI: 10.1111/nph.19132] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/20/2023] [Indexed: 07/25/2023]
Abstract
Wood performs several functions to ensure tree survival and carbon allocation to a finite stem volume leads to trade-offs among cell types. It is not known to what extent these trade-offs modify functional trade-offs and if they are consistent across climates and evolutionary lineages. Twelve wood traits were measured in stems and coarse roots across 60 adult angiosperm tree species from temperate, Mediterranean and tropical climates. Regardless of climate, clear trade-offs occurred among cellular fractions, but did not translate into specific functional trade-offs. Wood density was negatively related to hydraulic conductivity (Kth ) in stems and roots, but was not linked to nonstructural carbohydrates (NSC), implying a functional trade-off between mechanical integrity and transport but not with storage. NSC storage capacity was positively associated with Kth in stems and negatively in roots, reflecting a potential role for NSC in the maintenance of hydraulic integrity in stems but not in roots. Results of phylogenetic analyses suggest that evolutionary histories cannot explain covariations among traits. Trade-offs occur among cellular fractions, without necessarily modifying trade-offs in function. However, functional trade-offs are driven by coordinated changes among xylem cell types depending on the dominant role of each cell type in stems and roots.
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Affiliation(s)
- Guangqi Zhang
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
- SILVA, INRAE, Université de Lorraine, Agroparistech, Centre de Recherche Grand-Est Nancy, Champenoux, 54280, France
| | - Zhun Mao
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Pascale Maillard
- SILVA, INRAE, Université de Lorraine, Agroparistech, Centre de Recherche Grand-Est Nancy, Champenoux, 54280, France
| | - Loïc Brancheriau
- CIRAD, UPR BioWooEB, Montpellier, 34000, France
- BioWooEB, University of Montpellier, CIRAD, Montpellier, 34000, France
| | - Bastien Gérard
- SILVA, INRAE, Université de Lorraine, Agroparistech, Centre de Recherche Grand-Est Nancy, Champenoux, 54280, France
| | - Julien Engel
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Claire Fortunel
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Patrick Heuret
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Jean-Luc Maeght
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Jordi Martínez-Vilalta
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, E08193, Spain
- Universitat Autònoma Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, E08193, Spain
| | - Alexia Stokes
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
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23
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Takamura N, Hata Y, Matsumoto K, Kume T, Ueyama M, Kumagai T. El Niño-Southern Oscillation forcing on carbon and water cycling in a Bornean tropical rainforest. Proc Natl Acad Sci U S A 2023; 120:e2301596120. [PMID: 37812704 PMCID: PMC10589656 DOI: 10.1073/pnas.2301596120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 08/15/2023] [Indexed: 10/11/2023] Open
Abstract
Carbon dioxide and water vapor exchanges between tropical forest canopies and the atmosphere through photosynthesis, respiration, and evapotranspiration (ET) influence carbon and water cycling at the regional and global scales. Their inter- and intra-annual variations are sensitive to seasonal rhythms and longer-timescale tropical climatic events. In the present study, we assessed the El Niño-Southern Oscillation (ENSO) influence on ET and on the net ecosystem exchange (NEE), using eddy-covariance flux observations in a Bornean rainforest over a 10-y period (2010-2019) that included several El Niño and La Niña events. From flux model inversions, we inferred ecophysiological properties, notably the canopy stomatal conductance and "big-leaf" maximum carboxylation rate (Vcmax25_BL). Mean ET values were similar between ENSO phases (El Niño, La Niña, and neutral conditions). Conversely, the mean net ecosystem productivity was highest during La Niña events and lowest during El Niño events. Combining Shapley additive explanation calculations for nine controlling factors with a machine-learning algorithm, we determined that the primary factors for ET and NEE in the La Niña and neutral phases were incoming shortwave solar radiation and Vcmax25_BL, respectively, but that canopy stomatal conductance was the most significant factor for both ET and NEE in the El Niño phase. A combined stomatal-photosynthesis model approach further indicated that Vcmax25_BL differences between ENSO phases were the most significant controlling factor for canopy photosynthesis, emphasizing the strong need to account for ENSO-induced ecophysiological factor variations in model projections of the long-term carbon balance in Southeast Asian tropical rainforests.
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Affiliation(s)
- Naoya Takamura
- Department of Forest Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Tokyo113-8657, Japan
| | - Yoshiaki Hata
- Department of Forest Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Tokyo113-8657, Japan
| | - Kazuho Matsumoto
- Department of Subtropical Agro-Environmental Sciences, Faculty of Agriculture, University of the Ryukyus, Nishihara, Okinawa903-0213, Japan
| | - Tomonori Kume
- Shiiba Research Forest, Kyushu University, Shiiba, Miyazaki883-0402, Japan
| | - Masahito Ueyama
- Department of Environmental Sciences and Technology, Graduate School of Agriculture, Osaka Metropolitan University, Sakai599-8531, Japan
| | - Tomo’omi Kumagai
- Department of Forest Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Tokyo113-8657, Japan
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Aichi464-8601, Japan
- Water Resources Research Center, University of Hawai’i at Mānoa, Honolulu, HI96822
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24
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Sanchez-Martinez P, Mencuccini M, García-Valdés R, Hammond WM, Serra-Diaz JM, Guo WY, Segovia RA, Dexter KG, Svenning JC, Allen C, Martínez-Vilalta J. Increased hydraulic risk in assemblages of woody plant species predicts spatial patterns of drought-induced mortality. Nat Ecol Evol 2023; 7:1620-1632. [PMID: 37640766 PMCID: PMC10555820 DOI: 10.1038/s41559-023-02180-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 07/26/2023] [Indexed: 08/31/2023]
Abstract
Predicting drought-induced mortality (DIM) of woody plants remains a key research challenge under climate change. Here, we integrate information on the edaphoclimatic niches, phylogeny and hydraulic traits of species to model the hydraulic risk of woody plants globally. We combine these models with species distribution records to estimate the hydraulic risk faced by local woody plant species assemblages. Thus, we produce global maps of hydraulic risk and test for its relationship with observed DIM. Our results show that local assemblages modelled as having higher hydraulic risk present a higher probability of DIM. Metrics characterizing this hydraulic risk improve DIM predictions globally, relative to models accounting only for edaphoclimatic predictors or broad functional groupings. The methodology we present here allows mapping of functional trait distributions and elucidation of global macro-evolutionary and biogeographical patterns, improving our ability to predict potential global change impacts on vegetation.
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Affiliation(s)
- Pablo Sanchez-Martinez
- Universitat Autònoma de Barcelona, Cerdanyola del Valles, Barcelona, Spain.
- CREAF, Cerdanyola del Valles, Barcelona, Spain.
- School of GeoSciences, University of Edinburgh, Edinburgh, UK.
| | | | - Raúl García-Valdés
- CREAF, Cerdanyola del Valles, Barcelona, Spain
- Department of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, Móstoles, Madrid, Spain
| | | | - Josep M Serra-Diaz
- Université de Lorraine, AgroParisTech, INRAE, Nancy, France
- Eversource Energy Center, University of Connecticut, Storrs, CT, USA
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Wen-Yong Guo
- Research Center for Global Change and Complex Ecosystems & Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China
- Department of Biology, Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus C, Denmark
| | - Ricardo A Segovia
- Institute of Ecology and Biodiversity (IEB), Santiago, Chile
- Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Kyle G Dexter
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
- Royal Botanic Garden Edinburgh, Edinburgh, UK
| | - Jens-Christian Svenning
- Department of Biology, Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus C, Denmark
| | - Craig Allen
- Department of Geography and Environmental Studies, University of New Mexico, Albuquerque, NM, USA
| | - Jordi Martínez-Vilalta
- Universitat Autònoma de Barcelona, Cerdanyola del Valles, Barcelona, Spain
- CREAF, Cerdanyola del Valles, Barcelona, Spain
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25
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Martínez-Vilalta J, García-Valdés R, Jump A, Vilà-Cabrera A, Mencuccini M. Accounting for trait variability and coordination in predictions of drought-induced range shifts in woody plants. THE NEW PHYTOLOGIST 2023; 240:23-40. [PMID: 37501525 DOI: 10.1111/nph.19138] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023]
Abstract
Functional traits offer a promising avenue to improve predictions of species range shifts under climate change, which will entail warmer and often drier conditions. Although the conceptual foundation linking traits with plant performance and range shifts appears solid, the predictive ability of individual traits remains generally low. In this review, we address this apparent paradox, emphasizing examples of woody plants and traits associated with drought responses at the species' rear edge. Low predictive ability reflects the fact not only that range dynamics tend to be complex and multifactorial, as well as uncertainty in the identification of relevant traits and limited data availability, but also that trait effects are scale- and context-dependent. The latter results from the complex interactions among traits (e.g. compensatory effects) and between them and the environment (e.g. exposure), which ultimately determine persistence and colonization capacity. To confront this complexity, a more balanced coverage of the main functional dimensions involved (stress tolerance, resource use, regeneration and dispersal) is needed, and modelling approaches must be developed that explicitly account for: trait coordination in a hierarchical context; trait variability in space and time and its relationship with exposure; and the effect of biotic interactions in an ecological community context.
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Affiliation(s)
- Jordi Martínez-Vilalta
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Universitat Autònoma de Barcelona, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Raúl García-Valdés
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Forest Science and Technology Centre of Catalonia (CTFC), E25280, Solsona, Spain
- Department of Biology, Geology, Physics and Inorganic Chemistry, School of Experimental Sciences and Technology, Rey Juan Carlos University, E28933, Móstoles, Madrid, Spain
| | - Alistair Jump
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Albert Vilà-Cabrera
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Maurizio Mencuccini
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, E08010, Barcelona, Spain
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26
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Ishida A, Yamaji K, Nakano T, Ladpala P, Popradit A, Yoshimura K, Saiki ST, Maeda T, Yoshimura J, Koyama K, Diloksumpun S, Marod D. Comparative physiology of canopy tree leaves in evergreen and deciduous forests in lowland Thailand. Sci Data 2023; 10:601. [PMID: 37684226 PMCID: PMC10491629 DOI: 10.1038/s41597-023-02468-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 08/14/2023] [Indexed: 09/10/2023] Open
Abstract
The typical seasonally dry forests in Southeast Asia are the mixed deciduous forest (MDF), dry dipterocarp (deciduous) forest (DDF), and dry evergreen forest (DEF). We obtained 21 physiological traits in the top/sunlit leaves of 107, 65 and 51 tree species in MDF, DEF and DDF, respectively. Approximately 70%, 95% and 95% of canopy tree species which consist of MDF, DEF and DDF are sampled, respectively. Light-saturated photosynthetic rates (Asat) exhibit a positive correlation with foliar nitrogen (N) and phosphorus (P) on leaf mass and area bases across tree species. Decreased leaf mass-based P reduces the positive slope of the mass-based N and Asat relationship across species and habitats. The differences in nutrient and water use and leaf habits are well matched to the variation in soil properties among the forest types, highlighting the reliability of this comprehensive database for revealing the mechanism of niche segregation based on edaphic factors.
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Affiliation(s)
- Atsushi Ishida
- Center for Ecological Research, Kyoto University, Otsu, Shiga, 520-2113, Japan.
| | - Keiko Yamaji
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-0006, Japan
| | - Takashi Nakano
- Yamanashi Mount Fuji Research Institute, Kami-Yoshida, Fuji-Yoshida, Yamanashi, 403-0005, Japan
| | - Phanumard Ladpala
- Department of National Parks, Wildlife and Plant Conservation, Chatuchak, Bangkok, 10900, Thailand
| | - Ananya Popradit
- College of Innovation Management, Valaya Alongkorn University under the Royal Patronage, Klongluang, Pathum Thani, 13180, Thailand
| | - Kenichi Yoshimura
- Faculty of Agriculture, Yamagata University, Tsuruoka, Yamagata, 997-8555, Japan
| | - Shin-Taro Saiki
- Department of Forest Ecology, Forestry and Forest Products Research Institute, Tsukuba, Ibaraki, 305-8687, Japan
| | - Takahisa Maeda
- National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, 305-8569, Japan
| | - Jin Yoshimura
- Institute of Tropical Medicine, Nagasaki University, Sakamoto, Nagasaki, Nagasaki, 852-8523, Japan
- Faculty of Science, Tokyo Metropolitan University, Minami-Osawa, Hachioji, Tokyo, 192-0397, Japan
- The University Museum, The University of Tokyo, Hongo, Bunkyo, Tokyo, 113-0033, Japan
| | - Kohei Koyama
- Asahikawa campus, Hokkaido University of Education, Asahikawa, Hokkaido, 070-8621, Japan
| | - Sapit Diloksumpun
- Faculty of Forestry, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand
| | - Dokrak Marod
- Faculty of Forestry, Kasetsart University, Chatuchak, Bangkok, 10900, Thailand
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27
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Brum M, Vadeboncoeur M, Asbjornsen H, Puma Vilca BL, Galiano D, Horwath AB, Metcalfe DB. Ecophysiological controls on water use of tropical cloud forest trees in response to experimental drought. TREE PHYSIOLOGY 2023; 43:1514-1532. [PMID: 37209136 DOI: 10.1093/treephys/tpad070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 05/03/2023] [Accepted: 05/17/2023] [Indexed: 05/22/2023]
Abstract
Tropical montane cloud forests (TMCFs) are expected to experience more frequent and prolonged droughts over the coming century, yet understanding of TCMF tree responses to moisture stress remains weak compared with the lowland tropics. We simulated a severe drought in a throughfall reduction experiment (TFR) for 2 years in a Peruvian TCMF and evaluated the physiological responses of several dominant species (Clusia flaviflora Engl., Weinmannia bangii (Rusby) Engl., Weinmannia crassifolia Ruiz & Pav. and Prunus integrifolia (C. Presl) Walp). Measurements were taken of (i) sap flow; (ii) diurnal cycles of stem shrinkage, stem moisture variation and water-use; and (iii) intrinsic water-use efficiency (iWUE) estimated from foliar δ13C. In W. bangii, we used dendrometers and volumetric water content (VWC) sensors to quantify daily cycles of stem water storage. In 2 years of sap flow (Js) data, we found a threshold response of water use to vapor pressure deficit vapor pressure deficit (VPD) > 1.07 kPa independent of treatment, though control trees used more soil water than the treatment trees. The daily decline in water use in the TFR trees was associated with a strong reduction in both morning and afternoon Js rates at a given VPD. Soil moisture also affected the hysteresis strength between Js and VPD. Reduced hysteresis under moisture stress implies that TMCFs are strongly dependent on shallow soil water. Additionally, we suggest that hysteresis can serve as a sensitive indicator of environmental constraints on plant function. Finally, 6 months into the experiment, the TFR treatment significantly increased iWUE in all study species. Our results highlight the conservative behavior of TMCF tree water use under severe soil drought and elucidate physiological thresholds related to VPD and its interaction with soil moisture. The observed strongly isohydric response likely incurs a cost to the carbon balance of the tree and reduces overall ecosystem carbon uptake.
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Affiliation(s)
- Mauro Brum
- Department of Natural Resources & the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
| | - Matthew Vadeboncoeur
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Heidi Asbjornsen
- Department of Natural Resources & the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Beisit L Puma Vilca
- Facultad de Ciencias Biológicas, Universidad Nacional de San Antonio Abad del Cusco, Av. de La Cultura 773, Cusco, Cusco Province 08000, Peru
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Darcy Galiano
- Facultad de Ciencias Biológicas, Universidad Nacional de San Antonio Abad del Cusco, Av. de La Cultura 773, Cusco, Cusco Province 08000, Peru
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Aline B Horwath
- Asociación Civil Sin Fines De Lucro Para La Biodiversidad, Investigación Y Desarrollo Ambiental En Ecosistemas Tropicales (ABIDA), Urbanización Ucchullo Grande, Avenida Argentina F-9, Cusco, Perú
| | - Daniel B Metcalfe
- Department of Ecology & Environmental Science, Umeå University, KBC-huset, Linnaeus väg 6, Umeå 901 87, Sweden
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28
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Franklin O, Fransson P, Hofhansl F, Jansen S, Joshi J. Optimal balancing of xylem efficiency and safety explains plant vulnerability to drought. Ecol Lett 2023; 26:1485-1496. [PMID: 37330625 DOI: 10.1111/ele.14270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 05/05/2023] [Accepted: 05/05/2023] [Indexed: 06/19/2023]
Abstract
In vast areas of the world, forests and vegetation are water limited and plant survival depends on the ability to avoid catastrophic hydraulic failure. Therefore, it is remarkable that plants take hydraulic risks by operating at water potentials (ψ) that induce partial failure of the water conduits (xylem). Here we present an eco-evolutionary optimality principle for xylem conduit design that explains this phenomenon based on the hypothesis that conductive efficiency and safety are optimally co-adapted to the environment. The model explains the relationship between the tolerance to negative water potential (ψ50 ) and the environmentally dependent minimum ψ (ψmin ) across a large number of species, and along the xylem pathway within individuals of two species studied. The wider hydraulic safety margin in gymnosperms compared to angiosperms can be explained as an adaptation to a higher susceptibility to accumulation of embolism. The model provides a novel optimality-based perspective on the relationship between xylem safety and efficiency.
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Affiliation(s)
- Oskar Franklin
- International Institute for Applied Systems Analysis, Laxenburg, Austria
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Peter Fransson
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
- Interdisciplinary Center for Scientific Computing, Heidelberg University, Heidelberg, Germany
| | - Florian Hofhansl
- International Institute for Applied Systems Analysis, Laxenburg, Austria
| | | | - Jaideep Joshi
- International Institute for Applied Systems Analysis, Laxenburg, Austria
- Institute of Geography, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
- Complexity Science and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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29
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Fernández-de-Uña L, Martínez-Vilalta J, Poyatos R, Mencuccini M, McDowell NG. The role of height-driven constraints and compensations on tree vulnerability to drought. THE NEW PHYTOLOGIST 2023; 239:2083-2098. [PMID: 37485545 DOI: 10.1111/nph.19130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/07/2023] [Indexed: 07/25/2023]
Abstract
Frequent observations of higher mortality in larger trees than in smaller ones during droughts have sparked an increasing interest in size-dependent drought-induced mortality. However, the underlying physiological mechanisms are not well understood, with height-associated hydraulic constraints often being implied as the potential mechanism driving increased drought vulnerability. We performed a quantitative synthesis on how key traits that drive plant water and carbon economy change with tree height within species and assessed the implications that the different constraints and compensations may have on the interacting mechanisms (hydraulic failure, carbon starvation and/or biotic-agent attacks) affecting tree vulnerability to drought. While xylem tension increases with tree height, taller trees present a range of structural and functional adjustments, including more efficient water use and transport and greater water uptake and storage capacity, that mitigate the path-length-associated drop in water potential. These adaptations allow taller trees to withstand episodic water stress. Conclusive evidence for height-dependent increased vulnerability to hydraulic failure and carbon starvation, and their coupling to defence mechanisms and pest and pathogen dynamics, is still lacking. Further research is needed, particularly at the intraspecific level, to ascertain the specific conditions and thresholds above which height hinders tree survival under drought.
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Affiliation(s)
- Laura Fernández-de-Uña
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Jordi Martínez-Vilalta
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
| | - Rafael Poyatos
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- ICREA, Barcelona, 08010, Spain
| | - Nate G McDowell
- Pacific Northwest National Laboratory, Richland, WA, 99354, USA
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
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30
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Doughty CE, Keany JM, Wiebe BC, Rey-Sanchez C, Carter KR, Middleby KB, Cheesman AW, Goulden ML, da Rocha HR, Miller SD, Malhi Y, Fauset S, Gloor E, Slot M, Oliveras Menor I, Crous KY, Goldsmith GR, Fisher JB. Tropical forests are approaching critical temperature thresholds. Nature 2023; 621:105-111. [PMID: 37612501 DOI: 10.1038/s41586-023-06391-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 06/30/2023] [Indexed: 08/25/2023]
Abstract
The critical temperature beyond which photosynthetic machinery in tropical trees begins to fail averages approximately 46.7 °C (Tcrit)1. However, it remains unclear whether leaf temperatures experienced by tropical vegetation approach this threshold or soon will under climate change. Here we found that pantropical canopy temperatures independently triangulated from individual leaf thermocouples, pyrgeometers and remote sensing (ECOSTRESS) have midday peak temperatures of approximately 34 °C during dry periods, with a long high-temperature tail that can exceed 40 °C. Leaf thermocouple data from multiple sites across the tropics suggest that even within pixels of moderate temperatures, upper canopy leaves exceed Tcrit 0.01% of the time. Furthermore, upper canopy leaf warming experiments (+2, 3 and 4 °C in Brazil, Puerto Rico and Australia, respectively) increased leaf temperatures non-linearly, with peak leaf temperatures exceeding Tcrit 1.3% of the time (11% for more than 43.5 °C, and 0.3% for more than 49.9 °C). Using an empirical model incorporating these dynamics (validated with warming experiment data), we found that tropical forests can withstand up to a 3.9 ± 0.5 °C increase in air temperatures before a potential tipping point in metabolic function, but remaining uncertainty in the plasticity and range of Tcrit in tropical trees and the effect of leaf death on tree death could drastically change this prediction. The 4.0 °C estimate is within the 'worst-case scenario' (representative concentration pathway (RCP) 8.5) of climate change predictions2 for tropical forests and therefore it is still within our power to decide (for example, by not taking the RCP 6.0 or 8.5 route) the fate of these critical realms of carbon, water and biodiversity3,4.
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Affiliation(s)
- Christopher E Doughty
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA.
| | - Jenna M Keany
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Benjamin C Wiebe
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Camilo Rey-Sanchez
- Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC, USA
| | - Kelsey R Carter
- College of Forest Resources and Environmental Sciences, Michigan Technological University, Houghton, MI, USA
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Kali B Middleby
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Alexander W Cheesman
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Michael L Goulden
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Humberto R da Rocha
- Departamento de Ciencias Atmosfericas, Universidade de São Paulo, São Paulo, Brazil
| | - Scott D Miller
- Atmospheric Sciences Research Center, State University of New York at Albany, Albany, NY, USA
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Sophie Fauset
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | | | - Martijn Slot
- Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama
| | - Imma Oliveras Menor
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), CIRAD, CNRS, INRA, IRD, Université de Montpellier, Montpellier, France
| | - Kristine Y Crous
- Western Sydney University, Hawkesbury Institute for the Environment, Penrith, New South Wales, Australia
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
| | - Joshua B Fisher
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
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31
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Signori-Müller C, Galbraith D, Tavares JV, Reis SM, Diniz FC, Gilpin M, Marimon BS, van der Heijden GMF, Borges C, Cintra BBL, Mião S, Morandi PS, Nina A, Salas Yupayccana CA, Marca Zevallos MJ, Cosio EG, Junior BHM, Mendoza AM, Phillips O, Salinas N, Vasquez R, Mencuccini M, Oliveira RS. Tropical forest lianas have greater non-structural carbohydrate concentrations in the stem xylem than trees. TREE PHYSIOLOGY 2023:tpad096. [PMID: 37584458 DOI: 10.1093/treephys/tpad096] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 07/17/2023] [Accepted: 08/11/2023] [Indexed: 08/17/2023]
Abstract
Lianas (woody vines) are important components of tropical forests and are known to compete with host trees for resources, decrease tree growth and increase tree mortality. Given the observed increases in liana abundance in some forests and their impacts on forest function, an integrated understanding of carbon dynamics of lianas and liana-infested host trees is critical for improved prediction of tropical forest responses to climate change. Non-structural carbohydrates (NSC) are the main substrate for plant metabolism (e.g., growth, respiration), and have been implicated in enabling tree survival under environmental stress, but little is known of how they vary among life-forms or of how liana infestation impacts host tree NSC. We quantified stem total NSC (NSC) concentrations and its fractions (starch and soluble sugars) in trees without liana infestation, trees with more than 50% of the canopy covered by lianas, and the lianas infesting those trees. We hypothesized that i) liana infestation depletes NSC storage in host trees by reducing carbon assimilation due to competition for resources; ii) trees and lianas, which greatly differ in functional traits related to water transport and carbon uptake, would also have large differences in NSC storage, and that As water availability has a significant role in NSC dynamics of Amazonian tree species, we tested these hypotheses within a moist site in western Amazonia and a drier forest site in southern Amazonia. We did not find any difference in NSC, starch or soluble sugar concentrations between infested and non-infested trees, in either site. This result suggests that negative liana impact on trees may be mediated through mechanisms other than depletion of host tree NSC concentrations. We found lianas have higher stem NSC and starch than trees in both sites. The consistent differences in starch concentrations, a long term NSC reserve, between life forms across sites reflect differences in carbon gain and use of lianas and trees. Soluble sugar concentrations were higher in lianas than in trees in the moist site but indistinguishable between life forms in the dry site. The lack of difference in soluble sugars between trees and lianas in the dry site emphasize the importance of this NSC fraction for plant metabolism of plants occurring in water limited environments. Abstract in Portuguese and Spanish are available in the supplementary material.
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Affiliation(s)
- Caroline Signori-Müller
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Biologia Vegetal, University of Campinas, Campinas, Brazil
- School of Geography, University of Leeds, Leeds, UK
| | | | - Julia Valentim Tavares
- School of Geography, University of Leeds, Leeds, UK
- Department of Ecology and Genetics, Uppsala University, Sweden
| | - Simone Matias Reis
- Programa de Pós-Graduação da Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), UFAM-UNEMAT, Nova Xavantina, Brazil
- Laboratório de Ecologia Vegetal, Universidade do Estado de Mato Grosso, Nova Xavantina, Brazil
- School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, UK
| | | | | | - Beatriz Schwantes Marimon
- Programa de Pós-Graduação da Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), UFAM-UNEMAT, Nova Xavantina, Brazil
- Laboratório de Ecologia Vegetal, Universidade do Estado de Mato Grosso, Nova Xavantina, Brazil
| | | | - Camila Borges
- Programa de Pós-Graduação da Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), UFAM-UNEMAT, Nova Xavantina, Brazil
- Laboratório de Ecologia Vegetal, Universidade do Estado de Mato Grosso, Nova Xavantina, Brazil
| | - Bruno Barçante Ladvocat Cintra
- School of Geography, University of Leeds, Leeds, UK
- School of Geography, Earth and Environmental Sciences, University of Birmingham
| | - Sarah Mião
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Biologia Vegetal, University of Campinas, Campinas, Brazil
| | - Paulo S Morandi
- Programa de Pós-Graduação da Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), UFAM-UNEMAT, Nova Xavantina, Brazil
- Laboratório de Ecologia Vegetal, Universidade do Estado de Mato Grosso, Nova Xavantina, Brazil
| | - Alex Nina
- Pontificia Universidad Católica del Perú, Lima, Peru
| | | | - Manuel J Marca Zevallos
- Pontificia Universidad Católica del Perú, Lima, Peru
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
| | - Eric G Cosio
- Pontificia Universidad Católica del Perú, Lima, Peru
| | - Ben Hur Marimon Junior
- Programa de Pós-Graduação da Rede de Biodiversidade e Biotecnologia da Amazônia Legal (BIONORTE), UFAM-UNEMAT, Nova Xavantina, Brazil
- Laboratório de Ecologia Vegetal, Universidade do Estado de Mato Grosso, Nova Xavantina, Brazil
| | - Abel Monteagudo Mendoza
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Jardín Botánico de Missouri, Cusco, Peru
| | | | - Norma Salinas
- School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, UK
- Pontificia Universidad Católica del Perú, Lima, Peru
| | | | | | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
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32
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Song HQ, Wang YQ, Yan CL, Zeng WH, Chen YJ, Zhang JL, Liu H, Zhang QM, Zhu SD. Can leaf drought tolerance predict species abundance and its changes in tropical-subtropical forests? TREE PHYSIOLOGY 2023; 43:1319-1325. [PMID: 37154549 DOI: 10.1093/treephys/tpad058] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 04/14/2023] [Accepted: 05/01/2023] [Indexed: 05/10/2023]
Abstract
Climate change has resulted in an increase in drought severity in the species-rich tropical and subtropical forests of southern China. Exploring the spatiotemporal relationship between drought-tolerance trait and tree abundance provides a means to elucidate the impact of droughts on community assembly and dynamics. In this study, we measured the leaf turgor loss point (πtlp) for 399 tree species from three tropical forest plots and three subtropical forest plots. The plot area was 1 ha and tree abundance was calculated as total basal area per hectare according to the nearest community census data. The first aim of this study was to explore πtlp abundance relationships in the six plots across a range of precipitation seasonality. Additionally, three of the six plots (two tropical forests and one subtropical forest) had consecutive community censuses data (12-22 years) and the mortality ratios and abundance year slope of tree species were analyzed. The second aim was to examine whether πtlp is a predictor of tree mortality and abundance changes. Our results showed that tree species with lower (more negative) πtlp were more abundant in the tropical forests with relative high seasonality. However, πtlp was not related to tree abundance in the subtropical forests with low seasonality. Moreover, πtlp was not a good predictor of tree mortality and abundance changes in both humid and dry forests. This study reveals the restricted role of πtlp in predicting the response of forests to increasing droughts under climate change.
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Affiliation(s)
- Hui-Qing Song
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Yong-Qiang Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Chao-Long Yan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Wen-Hao Zeng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Ya-Jun Chen
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
| | - Jiao-Lin Zhang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
| | - Hui Liu
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, Guangdong, China
| | - Qian-Mei Zhang
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, Guangdong, China
- Dinghushan Forest Ecosystem Research Station, South China Botanical Garden, Chinese Academy of Sciences, Zhaoqing 526070, Guangdong, China
| | - Shi-Dan Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
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de Assis Prado CHB, de Brito Melo Trovão DM. The woody crown network model incorporates maximum height. Ecol Modell 2023. [DOI: 10.1016/j.ecolmodel.2023.110345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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Rowland L, Ramírez-Valiente JA, Hartley IP, Mencuccini M. How woody plants adjust above- and below-ground traits in response to sustained drought. THE NEW PHYTOLOGIST 2023. [PMID: 37306017 DOI: 10.1111/nph.19000] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/01/2023] [Indexed: 06/13/2023]
Abstract
Future increases in drought severity and frequency are predicted to have substantial impacts on plant function and survival. However, there is considerable uncertainty concerning what drought adjustment is and whether plants can adjust to sustained drought. This review focuses on woody plants and synthesises the evidence for drought adjustment in a selection of key above-ground and below-ground plant traits. We assess whether evaluating the drought adjustment of single traits, or selections of traits that operate on the same plant functional axis (e.g. photosynthetic traits) is sufficient, or whether a multi-trait approach, integrating across multiple axes, is required. We conclude that studies on drought adjustments in woody plants might overestimate the capacity for adjustment to drier environments if spatial studies along gradients are used, without complementary experimental approaches. We provide evidence that drought adjustment is common in above-ground and below-ground traits; however, whether this is adaptive and sufficient to respond to future droughts remains uncertain for most species. To address this uncertainty, we must move towards studying trait integration within and across multiple axes of plant function (e.g. above-ground and below-ground) to gain a holistic view of drought adjustments at the whole-plant scale and how these influence plant survival.
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Affiliation(s)
- Lucy Rowland
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RJ, UK
| | | | - Iain P Hartley
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RJ, UK
| | - Maurizio Mencuccini
- CREAF, Campus de Bellaterra (UAB), Cerdanyola del Vallés, Barcelona, 08193, Spain
- ICREA, Barcelona, 08010, Spain
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35
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Simioni PF, Emilio T, Giles AL, Viana de Freitas G, Silva Oliveira R, Setime L, Pierre Vitoria A, Pireda S, Vieira da Silva I, Da Cunha M. Anatomical traits related to leaf and branch hydraulic functioning on Amazonian savanna plants. AOB PLANTS 2023; 15:plad018. [PMID: 37214224 PMCID: PMC10198777 DOI: 10.1093/aobpla/plad018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 04/23/2023] [Indexed: 05/24/2023]
Abstract
Amazonian savannas are isolated patches of open habitats found within the extensive matrix of Amazonian tropical forests. There remains limited evidence on how Amazonian plants from savannas differ in the traits related to drought resistance and water loss control. Previous studies have reported several xeromorphic characteristics of Amazonian savanna plants at the leaf and branch levels that are linked to soil, solar radiation, rainfall and seasonality. How anatomical features relate to plant hydraulic functioning in this ecosystem is less known and instrumental if we want to accurately model transitions in trait states between alternative vegetation in Amazonia. In this context, we combined studies of anatomical and hydraulic traits to understand the structure-function relationships of leaf and wood xylem in plants of Amazonian savannas. We measured 22 leaf, wood and hydraulic traits, including embolism resistance (as P50), Hydraulic Safety Margin (HSM) and isotope-based water use efficiency (WUE), for the seven woody species that account for 75% of the biomass of a typical Amazonian savanna on rocky outcrops in the state of Mato Grosso, Brazil. Few anatomical traits are related to hydraulic traits. Our findings showed wide variation exists among the seven species studied here in resistance to embolism, water use efficiency and structural anatomy, suggesting no unique dominant functional plant strategy to occupy an Amazonian savanna. We found wide variation in resistance to embolism (-1.6 ± 0.1 MPa and -5.0 ± 0.5 MPa) with species that are less efficient in water use (e.g. Kielmeyera rubriflora, Macairea radula, Simarouba versicolor, Parkia cachimboensis and Maprounea guianensis) showing higher stomatal conductance potential, supporting xylem functioning with leaf succulence and/or safer wood anatomical structures and that species that are more efficient in water use (e.g. Norantea guianensis and Alchornea discolor) can exhibit riskier hydraulic strategies. Our results provide a deeper understanding of how branch and leaf structural traits combine to allow for different hydraulic strategies among coexisting plants. In Amazonian savannas, this may mean investing in buffering water loss (e.g. succulence) at leaf level or safer structures (e.g. thicker pit membranes) and architectures (e.g. vessel grouping) in their branch xylem.
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Affiliation(s)
| | - Thaise Emilio
- Programa Nacional de Pós-Doutorado (PNPD), Programa de Pós-Graduação em Ecologia, Instituto de Biologia, UNICAMP, Campinas, Brasil
| | - André L Giles
- Instituo Nacional de Pesquisa da Amazonia (INPA), Manaus, Amazonas, Brasil
- Departamento de Fitotecnia, Centro de Ciências Agrárias, Universidade Federal de Santa Catarina, Florianópolis, Brasil
| | - Gustavo Viana de Freitas
- Laboratório de Ciências Ambientais, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | | | - Lara Setime
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Angela Pierre Vitoria
- Laboratório de Ciências Ambientais, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Saulo Pireda
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Ivone Vieira da Silva
- Laboratório de Biologia Vegetal, Universidade do Estado do Mato Grosso, Alta Floresta, MT, Brasil
| | - Maura Da Cunha
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
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36
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Ferreira IJM, Campanharo WA, Fonseca MG, Escada MIS, Nascimento MT, Villela DM, Brancalion P, Magnago LFS, Anderson LO, Nagy L, Aragão LEOC. Potential aboveground biomass increase in Brazilian Atlantic Forest fragments with climate change. GLOBAL CHANGE BIOLOGY 2023; 29:3098-3113. [PMID: 36883779 DOI: 10.1111/gcb.16670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 02/03/2023] [Indexed: 05/03/2023]
Abstract
Fragmented tropical forest landscapes preserve much of the remaining biodiversity and carbon stocks. Climate change is expected to intensify droughts and increase fire hazard and fire intensities, thereby causing habitat deterioration, and losses of biodiversity and carbon stock losses. Understanding the trajectories that these landscapes may follow under increased climate pressure is imperative for establishing strategies for conservation of biodiversity and ecosystem services. Here, we used a quantitative predictive modelling approach to project the spatial distribution of the aboveground biomass density (AGB) by the end of the 21st century across the Brazilian Atlantic Forest (AF) domain. To develop the models, we used the maximum entropy method with projected climate data to 2100, based on the Intergovernmental Panel on Climate Change Representative Concentration Pathway (RCP) 4.5 from the fifth Assessment Report. Our AGB models had a satisfactory performance (area under the curve > 0.75 and p value < .05). The models projected a significant increase of 8.5% in the total carbon stock. Overall, the projections indicated that 76.9% of the AF domain would have suitable climatic conditions for increasing biomass by 2100 considering the RCP 4.5 scenario, in the absence of deforestation. Of the existing forest fragments, 34.7% are projected to increase their AGB, while 2.6% are projected to have their AGB reduced by 2100. The regions likely to lose most AGB-up to 40% compared to the baseline-are found between latitudes 13° and 20° south. Overall, although climate change effects on AGB vary latitudinally for the 2071-2100 period under the RCP 4.5 scenario, our model indicates that AGB stocks can potentially increase across a large fraction of the AF. The patterns found here are recommended to be taken into consideration during the planning of restoration efforts, as part of climate change mitigation strategies in the AF and elsewhere in Brazil.
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Affiliation(s)
| | | | | | | | - Marcelo Trindade Nascimento
- Laboratório de Ciências Ambientais, LCA, Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, Brazil
| | - Dora M Villela
- Laboratório de Ciências Ambientais, LCA, Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, Brazil
| | - Pedro Brancalion
- Department of Forest Sciences, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, Brazil
| | | | - Liana Oighenstein Anderson
- National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN), Parque Tecnológico de São José dos Campos, São José dos Campos, Brazil
| | - Laszlo Nagy
- Department of Animal Biology, University of Campinas, Campinas, Brazil
| | - Luiz E O C Aragão
- Remote Sensing Division, National Institute for Space Research (INPE), São José dos Campos, Brazil
- Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
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Tavares JV, Oliveira RS, Mencuccini M, Signori-Müller C, Pereira L, Diniz FC, Gilpin M, Marca Zevallos MJ, Salas Yupayccana CA, Acosta M, Pérez Mullisaca FM, Barros FDV, Bittencourt P, Jancoski H, Scalon MC, Marimon BS, Oliveras Menor I, Marimon BH, Fancourt M, Chambers-Ostler A, Esquivel-Muelbert A, Rowland L, Meir P, Lola da Costa AC, Nina A, Sanchez JMB, Tintaya JS, Chino RSC, Baca J, Fernandes L, Cumapa ERM, Santos JAR, Teixeira R, Tello L, Ugarteche MTM, Cuellar GA, Martinez F, Araujo-Murakami A, Almeida E, da Cruz WJA, Del Aguila Pasquel J, Aragāo L, Baker TR, de Camargo PB, Brienen R, Castro W, Ribeiro SC, Coelho de Souza F, Cosio EG, Davila Cardozo N, da Costa Silva R, Disney M, Espejo JS, Feldpausch TR, Ferreira L, Giacomin L, Higuchi N, Hirota M, Honorio E, Huaraca Huasco W, Lewis S, Flores Llampazo G, Malhi Y, Monteagudo Mendoza A, Morandi P, Chama Moscoso V, Muscarella R, Penha D, Rocha MC, Rodrigues G, Ruschel AR, Salinas N, Schlickmann M, Silveira M, Talbot J, Vásquez R, Vedovato L, Vieira SA, Phillips OL, Gloor E, Galbraith DR. Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests. Nature 2023; 617:111-117. [PMID: 37100901 PMCID: PMC10156596 DOI: 10.1038/s41586-023-05971-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 03/17/2023] [Indexed: 04/28/2023]
Abstract
Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, [Formula: see text]50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3-5, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters [Formula: see text]50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both [Formula: see text]50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth-mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.
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Affiliation(s)
- Julia Valentim Tavares
- School of Geography, University of Leeds, Leeds, UK.
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | | | - Caroline Signori-Müller
- School of Geography, University of Leeds, Leeds, UK
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Biologia Vegetal, University of Campinas, Campinas, Brazil
| | - Luciano Pereira
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | | | | | | | | | - Martin Acosta
- Programa de Pós-Graduação em Ecologia e Manejo de Recursos Naturais, Universidade Federal do Acre, Rio Branco, Brazil
| | | | - Fernanda de V Barros
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Ecologia, University of Campinas, Campinas, Brazil
| | - Paulo Bittencourt
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Halina Jancoski
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Marina Corrêa Scalon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
- Programa de Pós-Graduação em Ecologia e Conservação, Universidade Federal do Paraná, Curitiba, Brazil
| | - Beatriz S Marimon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Imma Oliveras Menor
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), CIRAD, CNRS, INRA, IRD, Université de Montpellier, Montpellier, France
| | - Ben Hur Marimon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Max Fancourt
- School of Geography, University of Leeds, Leeds, UK
| | | | - Adriane Esquivel-Muelbert
- School of Geography, University of Birmingham, Birmingham, UK
- Birmingham Institute of Forest Research (BIFoR), Birmingham, UK
| | - Lucy Rowland
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | | | - Alex Nina
- Pontificia Universidad Católica del Perú, Lima, Peru
| | | | - Jose S Tintaya
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
| | | | - Jean Baca
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | | | - Edwin R M Cumapa
- Instituto de Geociências, Faculdade de Meteorologia, Universidade Federal do Pará, Belém, Brazil
| | | | - Renata Teixeira
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
| | - Ligia Tello
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - Maira T M Ugarteche
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Gina A Cuellar
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Franklin Martinez
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Alejandro Araujo-Murakami
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Everton Almeida
- Instituto de Biodiversidade e Florestas, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | | | - Jhon Del Aguila Pasquel
- Universidad Nacional de la Amazonia Peruana (UNAP), Iquitos, Peru
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
| | - Luís Aragāo
- National Institute for Space Research (INPE), São José dos Campos-SP, Brazil
| | | | | | - Roel Brienen
- School of Geography, University of Leeds, Leeds, UK
| | - Wendeson Castro
- Laboratório de Botânica e Ecologia Vegetal, Universidade Federal do Acre, Rio Branco, Brazil
- SOS Amazônia, Programa Governança e Proteção da Paisagem Verde na Amazônia, Rio Branco-AC, Brazil
| | | | | | - Eric G Cosio
- Sección Química, Pontificia Universidad Católica del Perú, Lima, Peru
| | | | - Richarlly da Costa Silva
- Programa de Pós-Graduação em Ecologia e Manejo de Recursos Naturais, Universidade Federal do Acre, Rio Branco, Brazil
- Instituto Federal de Educação, Ciência e Tecnologia do Acre, Campus Baixada do Sol, Rio Branco, Brazil
| | - Mathias Disney
- Department of Geography, University College London, London, UK
| | - Javier Silva Espejo
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Departamento de Biología, Universidad de La Serena, La Serena, Chile
| | - Ted R Feldpausch
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | - Leandro Giacomin
- Departamento de Sistemática e Ecologia, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - Niro Higuchi
- Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
| | - Marina Hirota
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- Department of Physics, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Euridice Honorio
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
| | - Walter Huaraca Huasco
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Simon Lewis
- School of Geography, University of Leeds, Leeds, UK
- Department of Geography, University College London, London, UK
| | - Gerardo Flores Llampazo
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
- Universidad Nacional Jorge Basadre de Grohmann (UNJBG), Tacna, Peru
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Abel Monteagudo Mendoza
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Jardín Botánico de Missouri, Oxapampa, Peru
| | - Paulo Morandi
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Victor Chama Moscoso
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Jardín Botánico de Missouri, Oxapampa, Peru
| | - Robert Muscarella
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Deliane Penha
- Programa de Pós-Graduação em Biodiversidade, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Mayda Cecília Rocha
- Instituto de Ciências e Tecnologia das Águas, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Gleicy Rodrigues
- Programa de Pós-Graduação em Botânica, Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
| | | | - Norma Salinas
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- Sección Química, Pontificia Universidad Católica del Perú, Lima, Peru
| | - Monique Schlickmann
- Programa de Pós-Graduação em Biodiversidade, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Marcos Silveira
- Museu Universitário, Centro de Ciências Biológicas e da Natureza, Universidade Federal do Acre, Rio Branco, Brazil
| | - Joey Talbot
- Institute for Transport Studies, University of Leeds, Leeds, UK
| | | | - Laura Vedovato
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Simone Aparecida Vieira
- Núcleo de Estudos e Pesquisas Ambientais, Universidade Estadual de Campinas, Campinas, Brazil
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Xu H, Zhang Z, Oren R, Wu X. Hyposensitive canopy conductance renders ecosystems vulnerable to meteorological droughts. GLOBAL CHANGE BIOLOGY 2023; 29:1890-1904. [PMID: 36655411 DOI: 10.1111/gcb.16607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 01/07/2023] [Accepted: 01/11/2023] [Indexed: 05/28/2023]
Abstract
Increased meteorological drought intensity with rising atmospheric demand for water (hereafter vapor pressure deficit [VPD]) increases the risk of tree mortality and ecosystem dysfunction worldwide. Ecosystem-scale water-use strategy is increasingly recognized as a key factor in regulating drought-related ecosystem responses. However, the link between water-use strategy and ecosystem vulnerability to meteorological droughts is poorly established. Using the global flux observations, historic hydroclimatic data, remote-sensing products, and plant functional-trait archive, we identified potentially vulnerable ecosystems, examining how ecosystem water-use strategy, quantified by the percentage bias (δ) of the empirical canopy conductance sensitivity to VPD relative to the theoretical value, mediated ecosystem responses to droughts. We found that prevailing soil water availability substantially impacted δ in dryland regions where ecosystems with insufficient soil moisture usually showed conservative water-use strategy, while ecosystems in humid regions exhibited more pronounced climatic adaptability. Hyposensitive and hypersensitive ecosystems, classified based on δ falling below or above the theoretical sensitivity, respectively, achieved similar net ecosystem productivity during droughts, employing different structural and functional strategies. However, hyposensitive ecosystems, risking their hydraulic system with a permissive water-use strategy, were unable to recover from droughts as quickly as hypersensitive ones. Our findings highlight that processed-based models predicting current functions and future performance of vegetation should account for the greater vulnerability of hyposensitive ecosystems to intensifying atmospheric and soil droughts.
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Affiliation(s)
- Hang Xu
- Jixian National Forest Ecosystem Observation and Research Station, CNERN, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory of Soil and Water Conservation and Desertification Combating, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Zhiqiang Zhang
- Jixian National Forest Ecosystem Observation and Research Station, CNERN, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory of Soil and Water Conservation and Desertification Combating, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
| | - Ram Oren
- Nicholas School of the Environment and Pratt School of Engineering, Duke University, North Carolina, Durham, USA
- Department of Forest Science, University of Helsinki, Helsinki, Finland
| | - Xiaoyun Wu
- Jixian National Forest Ecosystem Observation and Research Station, CNERN, School of Soil and Water Conservation, Beijing Forestry University, Beijing, China
- Key Laboratory of Soil and Water Conservation and Desertification Combating, State Forestry and Grassland Administration, Beijing Forestry University, Beijing, China
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Ribeiro-Júnior NG, Marimon BH, Marimon BS, Cruz WJA, Silva IV, Galbraith DR, Gloor E, Phillips OL. Anatomical functional traits and hydraulic vulnerability of trees in different water conditions in southern Amazonia. AMERICAN JOURNAL OF BOTANY 2023; 110:e16146. [PMID: 36826405 DOI: 10.1002/ajb2.16146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 01/26/2023] [Accepted: 01/30/2023] [Indexed: 05/11/2023]
Abstract
PREMISE Understanding tree species' responses to drought is critical for predicting the future of tropical forests, especially in regions where the climate is changing rapidly. METHODS We compared anatomical and functional traits of the dominant tree species of two tropical forests in southern Amazonia, one on deep, well-drained soils (cerradão [CD]) and one in a riparian environment (gallery forest [GF]), to examine potential anatomical indicators of resistance or vulnerability to drought. RESULTS Leaves of CD species generally had a thicker cuticle, upper epidermis, and mesophyll than those of GF species, traits that are indicative of adaptation to water deficit. In the GF, the theoretical hydraulic conductivity of the stems was significantly higher, indicating lower investment in drought resistance. The anatomical functional traits of CD species indicate a greater potential for surviving water restriction compared to the GF. Even so, it is possible that CD species could also be affected by extreme climate changes due to the more water-limited environment. CONCLUSIONS In addition to the marked anatomical and functional differences between these phytophysiognomies, tree diversity within each is associated with a large range of hydraulic morphofunctional niches. Our results suggest the strong potential for floristic and functional compositional shifts under continued climate change, especially in the GF.
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Affiliation(s)
- Norberto G Ribeiro-Júnior
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Rua Prof. Dr. Renato Figueiro Varella, 78690-000, Nova Xavantina-MT, Brasil
- Diretoria Regional de Educação de Sinop, Secretaria de Estado de Educação de Mato Grosso, Rua dos Lírios, 78500-007, Sinop-MT, Brasil
| | - Ben Hur Marimon
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Rua Prof. Dr. Renato Figueiro Varella, 78690-000, Nova Xavantina-MT, Brasil
| | - Beatriz S Marimon
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Rua Prof. Dr. Renato Figueiro Varella, 78690-000, Nova Xavantina-MT, Brasil
| | - Wesley J A Cruz
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Rua Prof. Dr. Renato Figueiro Varella, 78690-000, Nova Xavantina-MT, Brasil
| | - Ivone V Silva
- Programa de Pós-graduação em Biodiversidade e Agroecossistemas, Universidade do Estado de Mato Grosso, Avenida Perimetral Rogério Silva, 4930, 78580-000, Alta Floresta-MT, Brasil
| | | | - Emanuel Gloor
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
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40
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Yao Y, Ciais P, Viovy N, Joetzjer E, Chave J. How drought events during the last century have impacted biomass carbon in Amazonian rainforests. GLOBAL CHANGE BIOLOGY 2023; 29:747-762. [PMID: 36285645 PMCID: PMC10100251 DOI: 10.1111/gcb.16504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
During the last two decades, inventory data show that droughts have reduced biomass carbon sink of the Amazon forest by causing mortality to exceed growth. However, process-based models have struggled to include drought-induced responses of growth and mortality and have not been evaluated against plot data. A process-based model, ORCHIDEE-CAN-NHA, including forest demography with tree cohorts, plant hydraulic architecture and drought-induced tree mortality, was applied over Amazonia rainforests forced by gridded climate fields and rising CO2 from 1901 to 2019. The model reproduced the decelerating signal of net carbon sink and drought sensitivity of aboveground biomass (AGB) growth and mortality observed at forest plots across selected Amazon intact forests for 2005 and 2010. We predicted a larger mortality rate and a more negative sensitivity of the net carbon sink during the 2015/16 El Niño compared with the former droughts. 2015/16 was indeed the most severe drought since 1901 regarding both AGB loss and area experiencing a severe carbon loss. We found that even if climate change did increase mortality, elevated CO2 contributed to balance the biomass mortality, since CO2 -induced stomatal closure reduces transpiration, thus, offsets increased transpiration from CO2 -induced higher foliage area.
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Affiliation(s)
- Yitong Yao
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Nicolas Viovy
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Emilie Joetzjer
- INRAE, Universite de Lorraine, AgroParisTech, UMR SilvaNancyFrance
| | - Jerome Chave
- Laboratoire Evolution et Diversité Biologique UMR 5174 CNRS, IRDUniversité Paul SabatierToulouseFrance
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Zhang YJ, Hochberg U, Rockwell FE, Ponomarenko A, Chen YJ, Manandhar A, Graham AC, Holbrook NM. Xylem conduit deformation across vascular plants: an evolutionary spandrel or protective valve? THE NEW PHYTOLOGIST 2023; 237:1242-1255. [PMID: 36307967 DOI: 10.1111/nph.18584] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
The hydraulic system of vascular plants and its integrity is essential for plant survival. To transport water under tension, the walls of xylem conduits must approximate rigid pipes. Against this expectation, conduit deformation has been reported in the leaves of a few species and hypothesized to function as a 'circuit breaker' against embolism. Experimental evidence is lacking, and its generality is unknown. We demonstrated the role of conduit deformation in protecting the upstream xylem from embolism through experiments on three species and surveyed a diverse selection of vascular plants for conduit deformation in leaves. Conduit deformation in minor veins occurred before embolism during slow dehydration. When leaves were exposed to transient increases in transpiration, conduit deformation was accompanied by large water potential differences from leaf to stem and minimal embolism in the upstream xylem. In the three species tested, collapsible vein endings provided clear protection of upstream xylem from embolism during transient increases in transpiration. We found conduit deformation in diverse vascular plants, including 11 eudicots, ginkgo, a cycad, a fern, a bamboo, and a grass species, but not in two bamboo and a palm species, demonstrating that the potential for 'circuit breaker' functionality may be widespread across vascular plants.
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Affiliation(s)
- Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- Climate Change Institute, University of Maine, Orono, ME, 04469, USA
| | - Uri Hochberg
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- ARO Volcani Center, Institute of Soil, Water and Environmental Sciences, Rishon Lezion, 7505101, Israel
| | - Fulton E Rockwell
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Alexandre Ponomarenko
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Ya-Jun Chen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Anju Manandhar
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Adam C Graham
- Center for Nanoscale Systems, Harvard University, Cambridge, MA, 02138, USA
| | - N Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
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42
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McCalmont J, Kho LK, Teh YA, Chocholek M, Rumpang E, Rowland L, Basri MHA, Hill T. Oil palm (Elaeis guineensis) plantation on tropical peatland in South East Asia: Photosynthetic response to soil drainage level for mitigation of soil carbon emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159356. [PMID: 36270353 DOI: 10.1016/j.scitotenv.2022.159356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 10/05/2022] [Accepted: 10/05/2022] [Indexed: 06/16/2023]
Abstract
While existing moratoria in Indonesia and Malaysia should preclude continued large-scale expansion of palm oil production into new areas of South-East Asian tropical peatland, existing plantations in the region remain a globally significant source of atmospheric carbon due to drainage driven decomposition of peatland soils. Previous studies have made clear the direct link between drainage depth and peat carbon decomposition and significant reductions in the emission rate of CO2 can be made by raising water tables nearer to the soil surface. However, the impact of such changes on palm fruit yield is not well understood and will be a critical consideration for plantation managers. Here we take advantage of very high frequency, long-term monitoring of canopy-scale carbon exchange at a mature oil palm plantation in Malaysian Borneo to investigate the relationship between drainage level and photosynthetic uptake and consider the confounding effects of light quality and atmospheric vapour pressure deficit. Canopy modelling from our dataset demonstrated that palms were exerting significantly greater stomatal control at deeper water table depths (WTD) and the optimum WTD for photosynthesis was found to be between 0.3 and 0.4 m below the soil surface. Raising WTD to this level, from the industry typical drainage level of 0.6 m, could increase photosynthetic uptake by 3.6 % and reduce soil surface emission of CO2 by 11 %. Our study site further showed that despite being poorly drained compared to other planting blocks at the same plantation, monthly fruit bunch yield was, on average, 14 % greater. While these results are encouraging, and at least suggest that raising WTD closer to the soil surface to reduce emissions is unlikely to produce significant yield penalties, our results are limited to a single study site and more work is urgently needed to confirm these results at other plantations.
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Affiliation(s)
- Jon McCalmont
- College of Life and Environmental Science, University of Exeter, Streatham Campus, Rennes Drive, Exeter EX4 4RJ, UK; School of Biological Sciences, University of Aberdeen, King's College, Aberdeen AB24 3FX, UK.
| | - Lip Khoon Kho
- Peat Ecosystem and Biodiversity Unit, Biology and Sustainability Research Division, Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia; Economic Planning Unit, Sarawak Chief Minister's Dept., 93502 Kuching, Sarawak, Malaysia
| | - Yit Arn Teh
- School of Natural and Environmental Science, Newcastle University, Drummond Building, Newcastle-upon-Tyne NE1 7RU, UK
| | - Melanie Chocholek
- Dept. Earth and Environmental Science, University of St. Andrews, Irvine Building, North Street, St. Andrews KY16 9AL, UK
| | - Elisa Rumpang
- Peat Ecosystem and Biodiversity Unit, Biology and Sustainability Research Division, Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia
| | - Lucy Rowland
- College of Life and Environmental Science, University of Exeter, Streatham Campus, Rennes Drive, Exeter EX4 4RJ, UK
| | - Mohd Hadi Akbar Basri
- College of Life and Environmental Science, University of Exeter, Streatham Campus, Rennes Drive, Exeter EX4 4RJ, UK; Dept. of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Tim Hill
- College of Life and Environmental Science, University of Exeter, Streatham Campus, Rennes Drive, Exeter EX4 4RJ, UK
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Induced drought strongly affects richness and composition of ground-dwelling ants in the eastern Amazon. Oecologia 2023; 201:299-309. [PMID: 36645473 DOI: 10.1007/s00442-023-05316-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/05/2023] [Indexed: 01/17/2023]
Abstract
Species loss in tropical regions is forecast to occur under environmental change scenarios of low precipitation. One of the main questions is how drought will affect invertebrates, a key group for ecosystem functioning. We use 1 year of data from a long-term rainwater exclusion experiment in primary Amazonian rainforest to test whether induced water stress and covarying changes in soil moisture, soil respiration, and tree species richness, diversity, size, and total biomass affected species richness and composition (relative abundance) of ground-dwelling ants. Data on ant abundance and environmental variables were collected at two sites (control and experimental) in the Eastern Amazon. Since 2002, drought has been induced in the experimental plot by excluding 50% of normal rainfall. Ant species richness in the experiment plot was reduced and some generalist species responded positively. Ant species richness also increased in the experimental plot with increasing diversity of the plant species of the leaf litter. The relative abundance of ants differed between plots. The experimental plot was characterized by a higher frequency of generalist and other species that appeared to be favored by the reduction in rainfall. Between-plot comparisons suggested loss and changes in ant species composition in tropical forests were affected by increasing dryness. These changes could ultimately lead to cascading effects on ecosystem processes and the services they mediate.
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Song Y, Jin G. Do Tree Size and Tree Shade Tolerance Affect the Photosynthetic Capacity of Broad-Leaved Tree Species? PLANTS (BASEL, SWITZERLAND) 2023; 12:523. [PMID: 36771608 PMCID: PMC9921863 DOI: 10.3390/plants12030523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/15/2023] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
(1) Background: leaf structure traits are closely related to leaf photosynthesis, reflecting the ability of trees to obtain external resources in the process of growth. (2) Methods: We studied the morphological, chemical, anatomical, stomatal traits and maximum net photosynthetic rate of six broad-leaf species in northern temperate mixed broad-leaved Korean pine (Pinus koraiensis) forest. (3) Aim: To investigate whether there are differences in leaf structural traits of trees with different shade tolerances and different sizes and the effects of these differences on leaf photosynthetic capacity. (4) Results: the effects of leaf structure traits on leaf photosynthesis were different among trees with different shade tolerances or different sizes. Under the condition of light saturation, the net photosynthetic rate, nitrogen use efficiency, phosphorus use efficiency and stomatal conductance of shade-intolerant trees or small trees were higher than those of shade-tolerant trees or large trees. (5) Conclusions: the shade tolerance of tree species or the size of trees affect the traits of leaf structure and indirectly affect the photosynthetic ability of plants. When constructing the leaf trait-photosynthesis model, the shade tolerance and tree size of tree species should be taken into account.
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Affiliation(s)
- Yuhan Song
- Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
| | - Guangze Jin
- Center for Ecological Research, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
- Northeast Asia Biodiversity Research Center, Northeast Forestry University, Harbin 150040, China
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45
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Chen YJ, Maenpuen P, Zhang JL, Zhang YJ. Remaining uncertainties in the Pneumatic method. THE NEW PHYTOLOGIST 2023; 237:384-391. [PMID: 36537302 DOI: 10.1111/nph.18530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 10/01/2022] [Indexed: 06/17/2023]
Affiliation(s)
- Ya-Jun Chen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- Yuanjiang Savanna Ecosystem Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Yuanjiang, Yunnan, 653300, China
| | - Phisamai Maenpuen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiao-Lin Zhang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
- Climate Change Institute, University of Maine, Orono, ME, 04469, USA
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46
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Docherty EM, Gloor E, Sponchiado D, Gilpin M, Pinto CAD, Junior HM, Coughlin I, Ferreira L, Junior JAS, da Costa ACL, Meir P, Galbraith D. Long-term drought effects on the thermal sensitivity of Amazon forest trees. PLANT, CELL & ENVIRONMENT 2023; 46:185-198. [PMID: 36230004 PMCID: PMC10092618 DOI: 10.1111/pce.14465] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/07/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
The continued functioning of tropical forests under climate change depends on their resilience to drought and heat. However, there is little understanding of how tropical forests will respond to combinations of these stresses, and no field studies to date have explicitly evaluated whether sustained drought alters sensitivity to temperature. We measured the temperature response of net photosynthesis, foliar respiration and the maximum quantum efficiency of photosystem II (Fv /Fm ) of eight hyper-dominant Amazonian tree species at the world's longest-running tropical forest drought experiment, to investigate the effect of drought on forest thermal sensitivity. Despite a 0.6°C-2°C increase in canopy air temperatures following long-term drought, no change in overall thermal sensitivity of net photosynthesis or respiration was observed. However, photosystem II tolerance to extreme-heat damage (T50 ) was reduced from 50.0 ± 0.3°C to 48.5 ± 0.3°C under drought. Our results suggest that long-term reductions in precipitation, as projected across much of Amazonia by climate models, are unlikely to greatly alter the response of tropical forests to rising mean temperatures but may increase the risk of leaf thermal damage during heatwaves.
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Affiliation(s)
- Emma M. Docherty
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | - Emanuel Gloor
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | - Daniela Sponchiado
- Departamento de Ciências Biológicas, Laboratório de Ecologia VegetalUniversidade do Estado de Mato GrossoNova XavantinaMato GrossoBrasil
| | - Martin Gilpin
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | | | | | - Ingrid Coughlin
- Departamento de Biologia, FFCLRPUniversidade de São PauloRibeirao PretoSão PauloBrasil
- College of Science, Research School of BiologyAustralian National UniversityCanberraAustralian Capital TerritorAustralia
| | | | | | - Antonio C. L. da Costa
- Instituto de GeosciênciasUniversidade Federaldo ParáBelémParáBrasil
- Museu Paraense Emílio GoeldiBelémParáBrasil
| | - Patrick Meir
- College of Science, Research School of BiologyAustralian National UniversityCanberraAustralian Capital TerritorAustralia
- College of Science and Engineering, School of GeoSciencesUniversity of EdinburghEdinburghUK
| | - David Galbraith
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
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Xu GQ, Chen TQ, Liu SS, Ma J, Li Y. Within-crown plasticity of hydraulic properties influence branch dieback patterns of two woody plants under experimental drought conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 854:158802. [PMID: 36115397 DOI: 10.1016/j.scitotenv.2022.158802] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 09/11/2022] [Accepted: 09/12/2022] [Indexed: 06/15/2023]
Abstract
In recent year, widespread declines of Populus bolleana Lauche trees (P. bolleana, which dieback from the top down) and Haloxylon ammodendron shrubs (H. ammodendron, which dieback starting from their outer canopy) have occurred. To investigate how both intra-canopy hydraulic changes and plasticity in hydraulic properties create differences in vulnerability between these two species, we conducted a drought simulation field experiment. We analyzed branch hydraulic vulnerability, leaf water potential (Ψ), photosynthesis (A), stomatal conductance (gs), non-structural carbohydrate (NSCs) contents and morphological traits of the plants as the plants underwent a partial canopy dieback. Our results showed that: (1) the hydraulic architecture was very different between the two life forms; (2) H. ammodendron exhibited a drought tolerance response with weak stomatal control, and thus a sharp decline in Ψ while P. bolleana showed a drought avoidance response with tighter stomatal control that maintained a relatively stable Ψ; (3) the Ψ of H. ammodendron showed relative consistent symptoms of drought stress with increasing plant stature, but the Ψ of P. bolleana showed greater drought stress in higher portions of the crown; (4) prolonged drought caused P. bolleana to consume and H. ammodendron to accumulate NSCs in the branches of their upper canopy. Thus, the prolonged drought caused the shoots of the upper canopy of P. bolleana to experience greater vulnerability leading to dieback of the upper branches first, while all the twigs of the outer canopy of H. ammodendron experienced nearly identical degrees of vulnerability, and thus dieback occurred uniformly. Our results indicate that intra-canopy hydraulic change and their plasticity under drought was the main cause of the observed canopy dieback patterns in both species. However, more work is needed to further establish that hydraulic limitation as a function of plant stature was the sole mechanism for causing the divergent canopy dieback patterns.
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Affiliation(s)
- Gui-Qing Xu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Tu-Qiang Chen
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shen-Si Liu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Ma
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Fukang Station of Desert Ecology, Chinese Academy of Sciences, Fukang 831505, China
| | - Yan Li
- State Key Lab of Subtropical Siviculture, Zhejiang A&F University, 666Wusu Street, Lin-An, Hangzhou 311300, China
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48
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Costa LDS, Vuralhan-Eckert J, Fromm J. Effect of Elevated CO 2 and Drought on Biomass, Gas Exchange and Wood Structure of Eucalyptus grandis. PLANTS (BASEL, SWITZERLAND) 2022; 12:148. [PMID: 36616277 PMCID: PMC9823954 DOI: 10.3390/plants12010148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Juvenile Eucalyptus grandis were exposed to drought and elevated CO2 to evaluate the independent and interactive effects on growth, gas exchange and wood structure. Trees were grown in a greenhouse at ambient and elevated CO2 (aCO2, 410 ppm; eCO2, 950 ppm), in combination with daily irrigation and cyclic drought during one growing season. The results demonstrated that drought stress limited intercellular CO2 concentration, photosynthesis, stomatal conductance, and transpiration, which correlated with a lower increment in height, stem diameter and biomass. Drought also induced formation of frequent and narrow vessels accompanied by a reduction in vessel lumen area. Conversely, elevated CO2 increased intercellular CO2 concentration as well as photosynthesis, and partially closed stomata, leading to a more efficient water use, especially under drought. There was a clear trend towards greater biomass accumulation at eCO2, although the results did not show statistical significance for this parameter. We observed an increase in vessel diameter and vessel lumen area at eCO2, and, contrarily, the vessel frequency decreased. Thus, we conclude that eCO2 delayed the effects of drought and potentialized growth. However, results on vessel anatomy suggest that increasing vulnerability to cavitation due to formation of larger vessels may counteract the beneficial effects of eCO2 under severe drought.
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Affiliation(s)
| | | | - Jörg Fromm
- Correspondence: (L.d.S.C.); (J.F.); Tel.: +49-40-73962-466 (L.d.S.C.)
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49
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Frei ER, Gossner MM, Vitasse Y, Queloz V, Dubach V, Gessler A, Ginzler C, Hagedorn F, Meusburger K, Moor M, Samblás Vives E, Rigling A, Uitentuis I, von Arx G, Wohlgemuth T. European beech dieback after premature leaf senescence during the 2018 drought in northern Switzerland. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:1132-1145. [PMID: 36103113 PMCID: PMC10092601 DOI: 10.1111/plb.13467] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 09/04/2022] [Indexed: 06/15/2023]
Abstract
During the particularly severe hot summer drought in 2018, widespread premature leaf senescence was observed in several broadleaved tree species in Central Europe, particularly in European beech (Fagus sylvatica L.). For beech, it is yet unknown whether the drought evoked a decline towards tree mortality or whether trees can recover in the longer term. In this study, we monitored crown dieback, tree mortality and secondary drought damage symptoms in 963 initially live beech trees that exhibited either premature or normal leaf senescence in 2018 in three regions in northern Switzerland from 2018 to 2021. We related the observed damage to multiple climate- and stand-related parameters. Cumulative tree mortality continuously increased up to 7.2% and 1.3% in 2021 for trees with premature and normal leaf senescence in 2018, respectively. Mean crown dieback in surviving trees peaked at 29.2% in 2020 and 8.1% in 2019 for trees with premature and normal leaf senescence, respectively. Thereafter, trees showed first signs of recovery. Crown damage was more pronounced and recovery was slower for trees that showed premature leaf senescence in 2018, for trees growing on drier sites, and for larger trees. The presence of bleeding cankers peaked at 24.6% in 2019 and 10.7% in 2020 for trees with premature and normal leaf senescence, respectively. The presence of bark beetle holes peaked at 22.8% and 14.8% in 2021 for trees with premature and normal leaf senescence, respectively. Both secondary damage symptoms occurred more frequently in trees that had higher proportions of crown dieback and/or showed premature senescence in 2018. Our findings demonstrate context-specific differences in beech mortality and recovery reflecting the importance of regional and local climate and soil conditions. Adapting management to increase forest resilience is gaining importance, given the expected further beech decline on dry sites in northern Switzerland.
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Affiliation(s)
- E. R. Frei
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- WSL Institute for Snow and Avalanche Research SLFDavos DorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
- Climate Change and Extremes in Alpine Regions Research Centre CERCDavos DorfSwitzerland
| | - M. M. Gossner
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
- Department of Environmental Systems ScienceETH ZurichZurichSwitzerland
| | - Y. Vitasse
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - V. Queloz
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - V. Dubach
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - A. Gessler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
- Department of Environmental Systems ScienceETH ZurichZurichSwitzerland
| | - C. Ginzler
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - F. Hagedorn
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - K. Meusburger
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
| | - M. Moor
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - E. Samblás Vives
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Autonomous University of Barcelona (UAB)Cerdanyola del VallesSpain
| | - A. Rigling
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
- Department of Environmental Systems ScienceETH ZurichZurichSwitzerland
| | - I. Uitentuis
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
| | - G. von Arx
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
- Oeschger Centre for Climate Change ResearchUniversity of BernBernSwitzerland
| | - T. Wohlgemuth
- Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- SwissForestLabBirmensdorfSwitzerland
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50
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Wang L, Li J, Wang Y, Xue H, Dai Y, Han Y. Interactive effect between tree ageing and trunk-boring pest reduces hydraulics and carbon metabolism in Hippophae rhamnoides. AOB PLANTS 2022; 14:plac051. [PMID: 36545298 PMCID: PMC9762721 DOI: 10.1093/aobpla/plac051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 10/21/2022] [Indexed: 06/17/2023]
Abstract
Sea-buckthorn (Hippophae rhamnoides) is widely distributed across the Eurasian continent. Recently sea-buckthorn has shown premature ageing and decline when confronted with water deficiency and Holcocerus hippophaecolus damage in northwest China and the Loess Plateau region. However, the physiological process of sea-buckthorn senescence in response to drought and pest damage is still unknown. In this study, 4-year-old (4y), 15-year-old normal growth (15yN) and 15-year-old seriously moth-damaged sea-buckthorn plants (15yH) were used as the research objects. The growth of branches and roots, branch water potential and percentage loss of conductivity (PLC), branch vulnerability to embolism (quantified by P50, xylem water potential at 50 % of PLC), branch xylem parenchyma cell viability, photosynthesis and the non-structural carbohydrate (NSC) content in branches and roots in dry and wet seasons were measured. The results showed that the length, basal diameter of 1-year-old branches and the leaf area of 4y trees were significantly larger than that of 15yN and 15yH trees, and the fine root density of 15yH trees was significantly lower than that of 15yN trees in all measured areas. The branch-specific hydraulic conductivity of 15yN and 15yH trees was only 50.2 % and 12.3 % of that of 4y trees, and the P50 of 4y, 15yH and 15yN trees was -3.69 MPa, -2.71 MPa and -1.15 MPa, respectively. The midday water potential and photosynthetic rate were highest in 4y trees, followed by 15yN and then 15yH trees in both the dry season and wet seasons, while branch PLC declined in the opposite direction (15yH trees highest, 4y trees lowest). The degree of PLC repair within a day was highest in 4y trees, followed by 15yN and then 15yH trees, and the viability of xylem cells was consistent with this pattern. The branch xylem starch and NSC content of 4y and 15yN trees were significantly higher than that of 15yH trees in the dry season, and the root starch and NSC content of 4y trees were significantly higher than that of 15yH trees in the two seasons. The above results suggest that the hydraulic properties of the normal elderly and seriously pest-damaged sea-buckthorn were significantly worse than in juvenile plants. Narrower early wood width and vessel density, high embolism vulnerability and weak embolism repair capacity led to the decline in water-conducting ability, and similarly further affected photosynthesis and the root NSC content. The decline in xylem parenchyma cell viability was the main reason for the limited embolism repair in the branches.
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Affiliation(s)
- Lin Wang
- Corresponding author’s e-mail address:
| | - Junpeng Li
- College of Forestry, Shanxi Agricultural University, Taigu, Shanxi 030801, P.R. China
| | - Yang Wang
- College of Forestry, Shanxi Agricultural University, Taigu, Shanxi 030801, P.R. China
| | - Hao Xue
- College of Forestry, Shanxi Agricultural University, Taigu, Shanxi 030801, P.R. China
| | - Yongxin Dai
- College of Forestry, Shanxi Agricultural University, Taigu, Shanxi 030801, P.R. China
| | - Youzhi Han
- College of Forestry, Shanxi Agricultural University, Taigu, Shanxi 030801, P.R. China
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